Loose-tube Fibre Optic Cable — OS2 / OM3 / OM4, 6 to 24 Strands, LSZH Jacket
Are you cabling a building, a datacenter or a horizontal backbone and need a robust multi-fibre cable, fire-rated and available in stock? Elfcam loose-tube cable groups all the fibres under a single LSZH jacket — more compact, faster to install, safer in case of fire.
Elfcam loose-tube cable — 250µm fibres under LSZH jacket, 6 to 24 strands available
Which loose-tube cable to choose?
Two main criteria guide the choice: the fibre type (OS2 single-mode or OM3/OM4 multimode) and the number of strands (6, 12 or 24). The table below summarises typical use cases.
OS2 — Single-mode
For long distances (up to several km), inter-building links and telecom networks. Compatible with PON, SFP+ 10G and SFP28 25G equipment.
- Long-distance campus backbone
- Datacenter ↔ technical room link
- Internal FTTH/GPON network
- Wavelength: 1310 / 1550 nm
OM3 — Multimode
Horizontal cabling and short backbone in commercial buildings. 10G compatible up to 300m, ideal for server rooms and enterprise LAN networks.
- Inter-floor cabling
- 10 Gigabit network up to 300m
- Progressive migration to OM4
- Bandwidth: 2000 MHz·km (OM3)
OM4 — High-density Multimode
Recommended standard for new 40G/100G datacenter deployments. Higher bandwidth than OM3, compatible with the same LC/SC connectors.
- 100G / 400G datacenter
- High-density distribution racks
- OM3 compatible (backward compatible)
- Bandwidth: 4700 MHz·km (OM4)
Quick decision matrix
| Need | Recommended type | Recommended strands | Max distance |
|---|---|---|---|
| Inter-building backbone | OS2 | 12 or 24 | > 1 km |
| Datacenter ↔ TR link | OS2 | 6 or 12 | > 500 m |
| 10G LAN building network | OM3 | 6 or 12 | up to 300 m |
| Office horizontal cabling | OM3 | 6 | up to 300 m |
| 100G / 400G datacenter | OM4 | 12 or 24 | up to 400 m |
| Future-proof new install | OM4 | 12 | up to 400 m |
For outdoor or buried installations, see our PE-armoured outdoor fibre cable. For patch cords and jumpers, see fibre optic cables.
Available lengths — all configurations
Each reference is available on reels cut to a fixed length. Check the table below to verify the availability of your type × strands × length combination before ordering.
| Type | Strands | 50 m | 100 m | 150 m | 200 m | 250 m | 300 m |
|---|---|---|---|---|---|---|---|
| OS2 Single-mode |
6 strands | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| 12 strands | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | |
| OM3 Multimode |
6 strands | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| 12 strands | ✓ | ✓ | ✓ | ✓ | — | ✓ | |
| 24 strands | ✓ | ✓ | ✓ | ✓ | — | ✓ | |
| OM4 Multimode |
6 strands | ✓ | ✓ | ✓ | ✓ | — | ✓ |
| 12 strands | ✓ | ✓ | ✓ | ✓ | — | ✓ | |
| 24 strands | ✓ | ✓ | ✓ | ✓ | — | — |
— : length not available in this configuration. For specific length or strand-count requirements, contact us.
OS2 — 6 and 12 strands
The most complete length range. Available from 50m to 300m, including 250m.
OM3 — 6, 12 and 24 strands
250m available in 6 strands only. For 12 and 24 strands: 50m to 300m (except 250m).
OM4 — 6, 12 and 24 strands
6 and 12 strands up to 300m. The 24-strand version is available from 50m to 200m.
Loose-tube cables by fibre type
OS2 Single-mode — LSZH
9/125µm, 6 and 12 strands, 50–300 m. Long distance, GPON, campus backbone.
-
Promo !
Elfcam® – Câble Structure Libre 250µm Fibre Optique Monomode OS2 – MV – LSZH(REF:13079)
8 comments 50M – 250M Le prix initial était : 49,99 €.39,99 €Le prix actuel est : 39,99 €. + Ce produit a plusieurs variations. Les options peuvent être choisies sur la page du produit
OM3 Multimode — LSZH
50/125µm, 6, 12 and 24 strands, 50–300 m. 10G over 300m, enterprise LAN cabling.
-
Promo !
Elfcam® – Câble Structure Libre 250µm Fibre Optique Multimode OM3 – MV – LSZH (REF:13113)
4 comments Le prix initial était : 69,99 €.65,99 €Le prix actuel est : 65,99 €. + Ce produit a plusieurs variations. Les options peuvent être choisies sur la page du produit
OM4 Multimode — LSZH
50/125µm, 6, 12 and 24 strands, 50–300 m. 100G/400G datacenter standard.
-
Promo !
Elfcam® – Câble Structure Libre 250µm Fibre Optique Multimode OM4 – MV – LSZH
2 comments Le prix initial était : 119,99 €.109,99 €Le prix actuel est : 109,99 €. + Ce produit a plusieurs variations. Les options peuvent être choisies sur la page du produit
Highlights of the Elfcam loose-tube cable
Loose-tube structure: more compact, faster to install
In a loose-tube cable, all 250µm fibres (primary coating only) are grouped under a single outer jacket. Unlike tight-buffered cables (900µm per fibre), the loose-tube structure is thinner, lighter and better suited to long runs and high fibre densities.
- 6mm diameter for 6 to 24 fibres
- Reduced weight: 31 kg/km (vs 50+ kg/km for tight-buffered cables)
- Easier pulling through trunking and conduits
- Termination via fusion-spliced pigtail or pre-polished connector
LSZH Jacket — EN 60332 Fire Safety
The LSZH (Low Smoke Zero Halogen) jacket is mandatory in public-access buildings (ERP), commercial buildings and server rooms. In case of fire, it does not release toxic halogens or dense smoke, unlike conventional PVC jackets.
- EN 60332-3-24 compliant (flame retardant)
- Halogen-free (HF) — safety for people and equipment
- Mandatory in enclosed technical spaces
- Compatible with ERP and datacenter requirements
Mechanical strength: 1500 N tensile
Despite its compact construction, the Elfcam cable offers robust mechanical strength for installation in trunking, cable trays and conduits.
- Tensile strength: 1500 N
- Crush resistance: 150 N/cm
- Minimum bend radius: 10× the diameter (≈ 60mm)
- Temperature range: –20°C to +60°C
Certified 250µm fibres — OS2 / OM3 / OM4
Each fibre meets international performance and geometry standards. OTDR results match the values expected by network integrator specifications.
- EN 60793-2-10 compliant (multimode) and EN 60793-2-50 (single-mode)
- EN 60794-1 compliant (optical cable)
- Compatible with EN 50173-1 / ISO 11801 cabling standards
- OTDR measurement and link certification possible
Chain diagram: from cable to certified optical link
For SFP modules compatible with OS2/OM3/OM4, see our optical modules range. For termination pigtails, see fibre pigtails.
Technical specifications — LSZH loose-tube cable
Construction and mechanical
| Parameter | Value |
|---|---|
| Fibre diameter | 250 µm (primary coating) |
| Cable diameter | 6 mm |
| Jacket thickness | 0.8 mm |
| Weight | 31 kg/km |
| Tensile strength | 1500 N |
| Crush resistance | 150 N/cm |
| Min. bend radius | 10× cable Ø (≈ 60 mm) |
| Temperature range (installation) | –5°C to +50°C |
| Temperature range (operation) | –20°C to +60°C |
| Jacket type | LSZH (Low Smoke Zero Halogen) |
Optical characteristics by type
| Parameter | OS2 | OM3 | OM4 |
|---|---|---|---|
| Core / cladding | 9/125 µm | 50/125 µm | 50/125 µm |
| Wavelength | 1310 / 1550 nm | 850 / 1300 nm | 850 / 1300 nm |
| Max attenuation | 0.4 dB/km (1310 nm) | 3.5 dB/km (850 nm) | 3.5 dB/km (850 nm) |
| Modal bandwidth | N/A | 2000 MHz·km | 4700 MHz·km |
| Max distance 10G | > 10 km | 300 m | 400 m |
| Max distance 100G | > 10 km | 100 m | 150 m |
| Fibre standard | EN 60793-2-50 | EN 60793-2-10 | EN 60793-2-10 |
| Cable standard | EN 60794-1 / EN 50173-1 / ISO 11801 | ||
Frequently asked questions — loose-tube fibre optic cable
1What is the difference between a loose-tube cable and a tight-buffered cable?
In a loose-tube cable, the fibres only have their 250µm primary coating and are loosely grouped inside the outer jacket. In a tight-buffered cable, each fibre is individually coated up to 900µm.
- Loose-tube: more compact (6mm for 24 fibres), lighter, suitable for long runs and conduit installations — fusion termination required
- Tight-buffered: more robust for individual fibre handling, suitable for patch cords and direct terminations without fusion
For internal cabling of a building or datacenter, loose-tube is the professional standard.
2Can I use this cable outdoors or in a trench?
No. Elfcam loose-tube cables (LSZH) are designed for indoor installation only. For outdoor environments, you need a cable with a PE jacket, rodent-resistant armour and UV resistance.
See our outdoor fibre cables range suitable for trench, buried conduit or exposed façade installations.
3OS2, OM3 or OM4: how to choose for a new project?
The basic rule:
- OS2: distance > 100m or telecom/GPON network. No practical distance limit. Compatible with all SFP equipment.
- OM3: existing 10G LAN network, distances < 300m. Good value for horizontal cabling.
- OM4: recommended for any new multimode deployment. Supports 100G over 150m, backward-compatible with OM3, similar price.
If in doubt about future speed upgrades, choose OM4.
4How do I terminate a loose-tube cable without a fusion splicer?
Terminating a loose-tube cable (250µm fibres) requires a fusion splicer. There is no reliable non-fusion solution for bare 250µm fibres.
The options:
- Fusion + SC/LC pigtail: standard solution, best performance (IL < 0.1 dB)
- Mechanical splice: temporary or field repair solution (typical IL 0.3–0.5 dB)
- Factory pre-commissioned: cable delivered with connectors installed under controlled conditions — not available on this product
For SC/LC-compatible pigtails, see Elfcam pigtails.
5Why is an LSZH jacket mandatory in certain premises?
The LSZH (Low Smoke Zero Halogen) jacket is required in ERP (public-access buildings), datacenters, enclosed technical spaces and any location where the imposed cabling standard is EN 50173 class D or higher.
In case of fire, a conventional PVC jacket releases corrosive hydrochloric acid (HCl) which damages electronic equipment within a radius of several metres. The LSZH jacket produces neither halogens nor opaque smoke, which facilitates evacuation and limits material damage.
6How many strands should I choose: 6, 12 or 24?
The golden rule: size at double the current need. A fibre cannot be added after pulling.
- 6 strands: point-to-point link, 2–3 devices, small installation
- 12 strands: standard for floor backbone (6 active + 6 spare), datacenter < 5 racks
- 24 strands: campus backbone, high-density datacenter, inter-building link with growth margin
7Is this cable compatible with Elfcam SFP+ 10G modules?
Yes. Once terminated (pigtail + LC or SC connector), the Elfcam loose-tube cable is compatible with all SFP, SFP+ and SFP28 modules available on elfcams.com.
- OS2: compatible with 1000Base-LX, 10GBase-LR, 25GBase-LR modules
- OM3: compatible with 10GBase-SR (850 nm) modules
- OM4: compatible with 10GBase-SR, 40GBase-SR4, 100GBase-SR4 modules
See the full range: Elfcam optical modules.
8What are the delivery times and available lengths?
Elfcam loose-tube cables are available in stock in France. Available lengths vary by type:
- OS2: 50m, 100m, 150m, 200m, 250m, 300m (6 and 12 strands)
- OM3: 50m, 100m, 150m, 200m, 250m, 300m (6, 12 and 24 strands)
- OM4: 50m, 100m, 150m, 200m, 300m (6, 12 and 24 strands)
Shipping within 24 business hours for orders placed before 2pm. Delivery in mainland France in 2–3 business days. For urgent projects, prioritise orders before 2pm.
See also
Fibre optic cables
SC/LC patch cords, simplex and duplex jumpers
SFP/SFP+ optical modules
1G to 100G, OS2 and OM3/OM4
Fibre optic pigtails
SC/APC, LC/UPC, ST — direct fusion
