FOSCYB5 Optical Fiber Cable Joint Closure

Deploying the FOSCYB5 dome closure across our regional FTTx distribution network solved several mid-span cable management challenges. Engineered with 5 total entry ports—comprising 1 main 25 mm oval port for uncut feeder cables and 4 round 16 mm branch ports—it allows our field crews to splice distribution drop lines without cutting primary feeder lines. The heat-shrinkable sealing system with thermoplastic rubber grommets forms a watertight seal that stands up to severe operating temperatures between -40°C and +65°C. Internally, the 4 dual-layer splice trays accommodate up to 96 bunchy fibers (24 fibers per dual-layer tray), while a dedicated fiber holding tray safely stores un-spliced loose tube buffer fibers.

At a reference price starting at just $23 USD, FirstFiber's FOSCYB5 delivers enterprise-grade environmental protection at a fraction of typical market costs. Featuring compact dimensions of 410 (H) × 190 (D) mm and a net weight of 2.3 to 2.5 kg, the unit is lightweight and easy for technicians to maneuver during overhead aerial installs. The closure arrives as a turnkey package complete with up to 4 splice trays, a loose tube storage tray, hanging hoops for pole and wall mounting, an M10 wrench, nylon ties, grounding wire, abrasive cloth, and protective aluminum-foil paper. Supporting up to 144 ribbon fibers, it provides an economical, scalable solution for expanding fiber infrastructure.

We standardized on the FOSCYB5 for underground pipeline, duct, and direct-buried splicing contracts due to its rigid Polycarbonate (PC) housing body. The high-impact plastic shell and plastic hoop clamp withstand heavy soil pressure and vibration without compromising seal integrity. We opted for the optional pressure testing valve to perform air tightness checks prior to underground trench backfilling. Whether configured for 24-core drop nodes or fully populated 96-core trunk splices, the FOSCYB5 provides superb cable organization, proper bend-radius protection, and long-term weather resistance.