GJXFH, GJXH, GJYXCH: How to Choose the Right FTTH Drop Cable for Your Project

Your supplier just quoted you five different drop cable model numbers — GJXFH, GJXH, GJYXCH, GJYXFCH, GJFJU. You need to answer one question before the PO can move: which one does this project actually need?

This guide is written for the person doing that decision. It skips the “what is a fiber drop cable” refresher (that lives in our Fiber Optic Drop Cable Guide) and gets straight to model-level selection.

If you buy for an FTTH rollout, resell drop cables to regional ISPs, or spec them into a project design, you will finish this in about ten minutes and walk out with a defensible model pick.

What the Letters in GJXFH Actually Mean

Chinese drop cable model codes follow the YD/T 1258 telecom standard. Once you learn the pattern, every future model name reads like a spec sheet:

Letter	Meaning	What it tells you about the cable
G	Communication-use optical cable	It is a telecom optical cable, not a copper or power hybrid
J	Indoor use (as a prefix)	Designed primarily for indoor deployment
Y	Outdoor use (as a prefix)	Designed for outdoor environments
X	Bow-type / butterfly cross-section	The flat, figure-eight-like profile
F	Strength member (context-dependent)	See caution note below
C	Self-supporting with integrated messenger	Has an internal steel or FRP wire to hold its own span
H	Sheath (as suffix)	Marks the outer jacket layer
J (mid-code, e.g. GJFJU)	Aramid / KFRP strength element	Fully non-metallic reinforcement
U	Non-metallic	No steel anywhere in the cross-section

Reading top to bottom:

• GJXFH = indoor bow-type cable with a strength member and LSZH sheath
• GJXH = indoor bow-type cable with a metal strength member and LSZH sheath (no “F” in older naming, present in newer conventions)
• GJYXCH = outdoor bow-type self-supporting cable with a steel messenger
• GJYXFCH = outdoor bow-type self-supporting cable with an FRP-based structure
• GJFJU = fully non-metallic indoor cable with aramid strength members

A word of caution on model names

Here is something no other buying guide will tell you: the letter “F” in GJXFH is not consistently interpreted across the Chinese manufacturing base. Some factories use it to mean FRP (non-metallic) strength members. Others use it as a generic marker for “reinforced” and still ship the cable with a steel wire inside.

We have seen both versions in the field. A drop cable labelledGJXFH on the outside can arrive with a 0.5 mm phosphated steel wire as its strength member. That is not a defect — it is a naming convention drift that has existed for years, especially among mid-tier OEMs.

Buyer’s reality check:
Never accept a drop cable model number alone. Always confirmstrength member material andjacket material in writing on the PO or the datasheet. Two suppliers can quote you “GJXFH” and ship physically different products. The datasheet is truth. The model code is a hint.

Steel, FRP, or Aramid: Choose the Strength Member Before the Model Number

Once you know the three families of strength members, the model number almost picks itself. Here is what changes across the three materials:

Property	Steel wire (phosphated / galvanized)	FRP (Fiber-Reinforced Plastic)	Aramid / KFRP
Tensile strength (typical)	Highest for a given diameter	Medium-high	High, closer to steel by weight
Conductivity	Conductive metal	Non-conductive dielectric	Non-conductive dielectric
Density / weight	Heaviest	Light	Lightest
Cost index (relative)	1.0 (baseline)	~1.15–1.30	~1.6–2.2
Bending fatigue	Can plastically deform if bent tightly	Resilient, springs back	Excellent, dominant fiber use
Cold-weather behaviour	Stable	Brittle at extreme sub-zero if low-grade	Stable across wide range
Fire behaviour with LSZH jacket	Metal residue after burn	Cleaner combustion	Cleaner combustion
Typical use case	Standard FTTH homes-passed, residential vertical, cost-driven projects	Non-metallic indoor environments, mixed EMI-sensitive buildings	Fully dielectric outdoor spans, elevator shafts, hospital MRI rooms, special-order deployments

The physics you actually need to remember

An optical fiber transmits data as light through a glass core. That process isfundamentally immune to electromagnetic interference — a fact you can quote to any customer who worries about “noise” on the line from nearby motors, transformers, or elevators. Light does not care about surrounding EMI.

But the cable around the fiber is a different story.

If the drop cable uses ametal strength member, that metal is a conductor. Under a nearby lightning strike, a high-voltage induction event, or a strong transient on a paralleled AC line, the metal element inside your drop cable can pick up induced current. When both ends of that cable terminate near active electronics (an ONT in the home, a distribution panel in a splice enclosure), the induced current has a path to ground — through your equipment.

This is why installers in lightning-prone regions, along high-voltage corridors, or near substations often specifynon-metallic drop cables (FRP or KFRP variants). The optical performance does not change. The risk profile does.

Pro tip for buyers:
If your customer is in Southeast Asia’s monsoon belt, along a rural high-voltage transmission corridor, in the Middle East desert with high dust-storm static, or specifying a hospital / substation / MRI project, ask them a single upstream question: “Is a fully non-metallic drop cable required or preferred?” That one question narrows five models down to two.

GJXFH — The Indoor Bow-Type Workhorse

GJXFH is what most residential FTTH rollouts install between the building’s distribution box and the subscriber’s ONT. It is designed for indoor conditions: temperature-stable environments, protected pathways, moderate pulling forces during initial installation.

Typical 1-fiber GJXFH datasheet (based on a real production spec):

Parameter	Value
Fiber count	1 (also 2 / 4-core versions)
Fiber type	G.657.A2 bend-insensitive single mode
Attenuation @1310 nm	≤ 0.4 dB/km
Attenuation @1550 nm	≤ 0.3 dB/km
Macro-bending loss @1625 nm, 7.5 mm × 1 turn	≤ 1.0 dB
Jacket dimensions	3.0 × 2.0 mm (LSZH, black or white)
Strength member	0.5 mm (steel or FRP, confirm on PO)
Long-term tensile load	40 N
Short-term tensile load	80 N
Min. bend radius (dynamic / static)	30 mm / 15 mm
Operating temperature	-40 to +70 °C
Storage temperature	-40 to +70 °C

Why G.657.A2 matters more than the price tag

Two drop cables can look identical on paper, differ by only $0.02 per meter, and still make a very different choice for your customer’s future.

G.657.A1 handles moderate bends but degrades sharply below ~10 mm radius.G.657.A2 — the fiber inside the specification above — holds a maximum 1.0 dB of macro-bending loss even at a 7.5 mm bend radius at 1625 nm.

Why does 1625 nm matter? Because that wavelength window is where the network diagnostic and futureXGS-PON 10G upgrade signals live. An ISP that deploys A1 today may face a costly forced re-cable when they upgrade to 10G FTTH, because the older fiber cannot hold signal integrity under the same bends. An A2 cable is, in effect, a low-cost insurance policy against the operator’s next network upgrade.

Distributor’s talking point:
When a wholesale buyer pushes back on your GJXFH price because a competitor is $0.03/m cheaper, ask which fiber grade the cheaper cable uses. If it is A1, you can honestly say: “That $0.03 saving becomes a full re-cabling cost when they move to XGS-PON in three years.” Buyers who buy for operators care about that math.

When not to use GJXFH

Indoor design means indoor use. Do not deploy GJXFH outdoors on an aerial pole or in a self-supporting span. The LSZH jacket is not formulated for continuous UV exposure, the thin cross-section will not survive ice load, and there is no messenger wire to carry the cable’s own weight over any distance.

If a buyer asks you whether “GJXFH outdoor” versions exist, the honest answer is no. What they need isGJYXCH orGJYXFCH — outdoor cables with an integrated messenger. Read on.

GJXH — Steel-Reinforced Indoor Bow-Type

GJXH is often used interchangeably with GJXFH in supplier catalogues, and the confusion is real. In our reading of the market, the practical distinction is this: GJXH consistently ships with a phosphated steel wire strength member and slightly higher tensile ratings than the FRP-marked variant.

Typical 2-fiber GJXH datasheet:

Parameter	Value
Fiber count	2 (also 1 / 4-core versions)
Fiber type	G.657.A2 (confirm A1 vs A2 on order)
Attenuation @1310 nm	≤ 0.4 dB/km
Jacket dimensions	3.1 × 2.0 mm (LSZH, black)
Strength member	2 × 0.45 mm phosphated steel wire
Long-term tensile load	100 N
Short-term tensile load	200 N
Min. bend radius (dynamic / static)	60 mm / 30 mm
Operating temperature	-20 to +60 °C

The most common mistake with GJXH

We have seen technicians pull GJXH through 20-meter conduit runs, up ceiling voids, or across short aerial spans. In every one of those cases the deployment worked on day one and produced customer complaints six months later — micro-fractures inside the fiber, gradual attenuation creep, and a service call to replace the run.

A 100 N long-term tensile rating means the cable can hold its own weight and moderate pulling forceonce installed and static. It does not mean you can drag it through 15 meters of conduit against friction. If your installer needs meaningful pulling force, spec a cable rated for it — usually GJYXCH at 300 N long-term, even for a short indoor-to-outdoor transition.

Real-world scenario:
A buyer in East Africa reported drop cable failures after three months of service. Root cause: their installer used GJXH indoor cable for a 40-meter run through a rooftop conduit because it was on hand. Within one rainy season the LSZH jacket had absorbed enough moisture at exposed conduit joints to induce microbending. The fix was a rework with GJYXCH — and a written material spec on every future PO.

GJYXCH — Self-Supporting Outdoor Drop for Aerial FTTH

GJYXCH is the outdoor workhorse: designed for aerial deployment between utility poles, engineered to hold its own weight over spans up to ~80 meters, and jacketed to survive UV, temperature swing, and moderate rain load.

Typical 2-fiber GJYXCH datasheet:

Parameter	Value
Fiber count	2 (custom up to 12-core)
Fiber type	G.652.D or G.657.A series
Attenuation @1310 nm	≤ 0.36 dB/km
Attenuation @1550 nm	≤ 0.22 dB/km
Jacket dimensions	5.0 × 2.0 mm (LSZH, black)
Structure	Flat cable + integrated steel messenger, “figure-8” cross-section
Steel messenger	1 × 1.0 mm
Steel strength members (in cable side)	2 × 0.4 mm phosphated steel
Long-term tensile load	300 N
Short-term tensile load	600 N
Max aerial span	≤ 80 m
Operating temperature	-20 to +60 °C

What “self-supporting” actually means

The word matters. A self-supporting drop cable carries its own dead weight plus wind and (in colder climates) ice load, without requiring a separate lashing wire. The integrated messenger inside GJYXCH is what does that work.

For spans up to ~80 meters this design is efficient and cheap. Beyond 80 meters — think longer road crossings, river crossings, or rural aerial runs between poles further apart — the messenger geometry no longer holds the required sag and tension. That is where ADSS cable takes over.

Two common misuses

Do not direct-bury GJYXCH. The jacket is not designed for soil contact, moisture pressure, or rodent load. For direct burial, spec an armored outdoor cable such as GYTA53.

Do not exceed the max span. We have watched installers hang GJYXCH across 100-meter road crossings “just this once” because ADSS was not on hand. Within one storm season, cable sag exceeded compliance limits and pole loading became a safety risk. Match the design to the span, not the calendar.

When You Need Fully Non-Metallic: Aramid (KFRP) and GJYXFCH

Two scenarios drive customers to fully non-metallic drop cables:

Scenario one — active EMI or lightning risk. Substations, high-voltage transmission corridors, telecom-power co-siting projects, and (in some regions) coastal areas with high atmospheric static. In these environments the customer specification often mandates dielectric drop cables to eliminate any induced-current path.

Scenario two — regulatory or contract mandate. Hospitals near MRI rooms, some airport / military / secure-facility deployments, and specific European telco frameworks that require dielectric last-mile cabling.

For those cases:

• GJYXFCH — outdoor self-supporting version with FRP-based structure instead of steel messenger
• GJFJU — fully non-metallic indoor bow-type with aramid (KFRP) strength members

Both variants are available on order rather than as standard stock. Lead times run 1–3 weeks longer than the steel-wire equivalents, and the price index sits at roughly 1.6–2.2× the corresponding metallic version. The buying decision should therefore be“is this project actually one of those two scenarios,” not“do we want non-metallic just to be safe.” Over-specification is a real cost driver.

The Drop Cable Decision Tree — 4 Questions, 1 Model

The decision reduces to four sequential questions. Ask them in this order and the correct model falls out:

1. Is the deployment indoor or outdoor?
   Indoor → GJXFH or GJXH · Outdoor → GJYXCH or GJYXFCH
2. For outdoor: is the cable installed aerially between poles, with no separate messenger wire?
   Yes → self-supporting variant (GJYXCH or GJYXFCH) · No → armored outdoor cable such as GYTA53
3. Is a fully non-metallic cable required (EMI zone, lightning-prone, hospital, contract-mandated dielectric)?
   Yes → FRP or KFRP version (GJXFH-FRP indoor, GJYXFCH outdoor, GJFJU for special deployments) · No → steel-reinforced version is fine
4. Is cost-per-meter more important than a premium feature set?
   Yes → steel wire strength member · No → FRP or KFRP for the longer-service-life scenarios above

Four questions. Five models. One picked cable.

Before You Sign the PO: A Drop Cable Buying Checklist

Print this section, share it with your procurement or engineering team, and use it every time you request a quote or receive a shipment.

Specification checklist (put these on the PO in writing)

• Model number and strength member material (never trust the model alone)
• Fiber count (1 / 2 / 4 / custom)
• Fiber grade — insist on G.657.A2 for any FTTH deployment that may be upgraded to XGS-PON
• Jacket material (LSZH for indoor and most modern outdoor; PE only where LSZH is not required)
• Jacket color (black is standard outdoor; white or grey may be requested for indoor visibility)
• Reel length (typical 2–3 km per drum; confirm before large orders)
• Print marking format (sequential meter marks, batch code, and any customer branding)
• Certifications required for the destination country (CPR for EU building applications, ANATEL for Brazil, UL/ETL for North American indoor risers)

Quality verification checklist (do these on receipt)

• Every reel should ship with a factory OTDR trace and attenuation report bearing a batch number
• Visually inspect the sheath for consistency, embedded print, and any color inconsistency
• Random-sample a 1-meter section: strip the sheath, confirm strength member matches PO spec
• Bend-test a sample at the rated static bend radius and re-measure loss on an OTDR (a 0.1 dB or greater jump warrants a batch review)

Red flags that should trigger a rejection or renegotiation

• Model number and physical construction do not match the PO
• LSZH sheath emits an obvious plastic smell when a sample is heat-tested (indicates non-compliant compound)
• No batch-level test data supplied with the shipment
• Metal strength member shows early oxidation before installation
• Print marking is smudged or missing at intervals — will fail acceptance testing on the customer side

Bottom Line — Match the Model to the Deployment

Buying a drop cable well is an act of translation. The customer says “we need FTTH last-mile,” which really means “we need the specific model that fits this deployment’s environment, tension profile, EMI risk, and lifecycle.” The decision tree above turns that translation into four questions.

The single most common mistake we see across the region is not overpaying — it is under-specifying. A GJXH indoor cable pulled through a rooftop conduit costs less on the invoice and costs more in the truck rolls it triggers. Spec the model to what the cable will actually experience over its service life, not to what feels cheapest on the day of the PO.

If you would like a printable side-by-side view covering all five models discussed above — you can download it from our FTTH Drop Cable resource hub. We update the sheet quarterly.

Frequently Asked Questions About FTTH Drop Cable Model Selection

What is the difference between GJXFH and GJXH?

GJXFH and GJXH are both indoor bow-type drop cables. In the strict Chinese YD/T 1258 naming convention, the letter F in GJXFH indicates a non-metallic FRP strength member, while GJXH indicates a metallic (usually phosphated steel) strength member. In practice, factory naming varies — some suppliers ship a cable labeled GJXFH with a steel wire inside. Always confirm the strength member material on your purchase order, not just the model code.

What does GJXFH stand for?

Each letter encodes a physical attribute under YD/T 1258.G stands for communication-use optical cable, J marks it as an indoor cable, X identifies the bow-type (butterfly) cross-section, F identifies the strength member category, andH identifies the outer jacket. Read together, GJXFH means an indoor bow-type single-fiber drop cable with a reinforced strength member and an outer sheath (typically LSZH).

Can I use indoor drop cable such as GJXFH outdoors?

No. Indoor drop cables use LSZH jackets that are not UV-stabilised for continuous sunlight exposure, and their cross-section is not designed to survive ice load, wind stress, or outdoor moisture. For aerial FTTH deployments between poles, use GJYXCH (steel messenger) or GJYXFCH (non-metallic messenger). For duct or direct-burial use, specify an armored outdoor cable such as GYTA53.

Is FRP or steel wire better for a drop cable strength member?

Neither is universally better — the correct choice depends on the deployment. Steel wire delivers higher tensile strength per dollar and remains the most cost-efficient option for standard indoor residential FTTH. FRP (non-conductive fiber-reinforced plastic) is the correct pick for environments with active EMI, lightning risk, or proximity to high-voltage lines, where a metallic path to ground inside the cable would create a hazard for the connected ONT or distribution equipment.

Are optical drop cables affected by nearby high-voltage lines or lightning?

The optical fiber inside the cable is fundamentally immune to electromagnetic interference — light does not respond to EMI. However, if the cable uses ametal strength member, that metal can pick up induced current from a nearby lightning strike or strong AC transient, and that current has a path through the cable ends to your terminating equipment. For deployments near substations, transmission corridors, or in lightning-prone regions, specify a fully non-metallic (FRP or KFRP) variant.

What is a self-supporting FTTH drop cable?

A self-supporting drop cable has an integrated messenger element — usually a steel wire in GJYXCH or an FRP rod in GJYXFCH — that carries the cable’s own weight across an aerial span between two support points, typically utility poles. This eliminates the need for a separate lashing wire, simplifying aerial installation. Typical maximum span is ~80 meters; longer runs should use ADSS cable instead.

What is the maximum aerial span for a GJYXCH drop cable?

Approximately 80 meters between support points, under standard conditions. Beyond that distance, cable sag exceeds compliance limits under wind and ice load, and the messenger tension can compromise pole hardware. For spans between 80 and 200+ meters, deploy ADSS cable, which is engineered for longer aerial runs.

Can I bury GJYXCH cable directly underground?

No. GJYXCH is jacketed for aerial exposure to UV and weather, not for soil contact, ground moisture pressure, or rodent protection. For direct burial, use an armored cable such as GYTA53 with a steel-tape armor and appropriate sheathing.

How long is a standard FTTH drop cable per reel?

Standard reel length is typically 2 to 3 kilometers for indoor GJXFH / GJXH and outdoor GJYXCH. Custom reel lengths and larger drums can be produced on order — confirm both the standard offering and any project-specific length requirement with your supplier before finalizing the PO.

What tensile strength does a drop cable actually need for my project?

It depends on the installation scenario, not on the cable name. Wall-run or short indoor deployments typically require 40–100 N long-term tension (GJXFH or GJXH). Conduit pulling, ceiling voids, and short aerial transitions require higher rated cables — even for short outdoor spans, spec GJYXCH at 300 N long-term. Under-speccing the tensile rating is the single most common cause of latent micro-fracture failures we see in the field.

How do I verify drop cable quality before accepting delivery?

Request a factory OTDR trace and attenuation report for every reel, keyed to the batch number. Visually inspect the sheath for consistent color, embedded print marking, and no material inconsistency. Random-sample a short section from each shipment, strip the sheath, and confirm that the strength member material physically matches your PO specification. Any mismatch between the PO and the actual construction should trigger an immediate quality dialogue with the supplier.

What fiber grade should I specify for future-proof FTTH deployments?

SpecifyG.657.A2 or higher. Older-generation G.657.A1 fiber shows significant macro-bending loss at bend radii below 10 mm, especially at 1625 nm — the wavelength window used for XGS-PON 10G FTTH network expansion. Deploying A1 today may force an operator into a costly network re-cable when they upgrade. A2 fiber holds ≤ 1.0 dB loss at a 7.5 mm bend radius at 1625 nm, effectively covering the operator’s next upgrade cycle at a marginal cost premium.