2m MPO to LC Breakout Fiber Cable, OS2 8 Fiber Single Mode, MPO/APC to LC/UPC, Plenum OFNP, Yellow

The CableLeader FB126-9CXX is an OS2 single mode breakout fiber cable that converts one MPO/APC connector into eight LC/UPC connectors arranged as four duplex pairs. Eight Corning SMF-28 Ultra fibers run inside a 3.0 mm yellow single-tube trunk, then fan out through a molded transition into 2.0 mm legs, each 500 mm long and color-coded for channel identification. The assembly gives single mode parallel-optics hardware a direct path into duplex LC equipment without an intermediate cassette.

The polish scheme is mixed by design, and each end goes to a different kind of port. The MPO end wears the green housing of APC polish: its 8-degree angled ferrule holds return loss at 60 dB minimum and mates only with APC ports — never force it into a flat-polish UPC receptacle, since the mismatched end-faces can be permanently damaged. The LC ends are standard blue-referenced UPC polish at 50 dB minimum return loss, matching the LC/UPC ports found on duplex transceivers and patch panels.

The MPO connector is a US Conec MTP Elite female (unpinned) built on a 12-position MT ferrule with eight fibers populated — four transmit, four receive, the exact count single mode parallel links use. Female gender mates directly with the pinned MPO receptacles on parallel-optics modules. Insertion loss is factory-limited to 0.35 dB at the MPO end and 0.20 dB at each LC connector, verified on every assembly at both 1310 nm and 1550 nm.

The jacket carries an OFNP plenum listing under UL file E486140 along with RoHS compliance. OFNP is the highest optical cable fire rating, permitted in air-handling plenums, drop ceilings, and raised floors, and substitutes freely where riser-rated cable is specified. Yellow follows the industry color convention for single mode cabling, and the G657A1 bend tolerance of SMF-28 Ultra keeps loss stable through tight cabinet routing.

Typical deployments break out a single mode parallel-optics port — commonly a PSM4-class 100G module — into four duplex LC links toward switches, servers, or LC panels, and connect APC trunk plant to UPC electronics inside fiber distribution frames. Single mode reach far exceeds multimode, so the same construction serves campus and building-to-building runs where an OM4 breakout cannot.

Compatibility & Ordering Information — FB126-9CXX mates with pinned single mode MPO/MTP APC ports, including PSM4-class parallel transceivers and APC cassette or panel connectors; the LC/UPC ends fit any standard LC port, duplex single mode optic, or adapter panel. Match polish at every port: green APC end to APC hardware, LC/UPC ends to UPC hardware only. The family is offered in lengths from 1 m through 30 m. For the multimode OM4 version of this breakout, see the FB124-4CXX family; MTP/APC trunk cables are available as FB125-9BXX (Type A) and FB127-9BXX (Type B).

Product Comparison: Single Mode OS2 Breakout vs Multimode OM4 Breakout

Both cables fan one 8-fiber parallel-optics connector out to four LC duplex pairs; the fiber class and polish decide which transceivers and distances they serve. The table summarizes the decision:

Select the OS2 single mode breakout for PSM4-class ports, long links, and headroom as speeds rise.
Select the OM4 multimode breakout for SR4-class ports on short in-hall runs. Fiber type and polish must match the ports at both ends — the green APC end of this cable never plugs into UPC hardware.

FAQ

What is the difference between APC and UPC polish on this cable?

APC ferrules are polished at an 8-degree angle and wear green housings; UPC ferrules are flat-polished and referenced blue. The angle deflects reflections into the cladding, which is why the MPO/APC end reaches 60 dB return loss versus 50 dB at the LC/UPC ends. The two polishes never intermate — APC connects only to APC, UPC only to UPC, and forcing them together can damage both ferrules.

Is this breakout compatible with 100G PSM4 transceivers?

Yes. PSM4-class modules transmit over four single mode fiber pairs through a pinned MPO/APC port, and this cable's female MPO/APC end mates with that port directly. The four LC/UPC duplex legs then land on duplex LC equipment or panels, splitting the parallel port into four independent links.

Why does this cable use 8 fibers on a 12-position connector?

Single mode parallel-optics links use exactly eight fibers — four transmit and four receive — so eight populated positions match the transceiver with no dark fiber terminated. The MT ferrule keeps its standard 12-position format for compatibility with common MPO adapters and cassettes, and the eight fibers exit as four LC duplex pairs.

How do I connect this cable — which end goes where?

The green MPO/APC end plugs into the angled-polish parallel port: transceiver, APC cassette, or APC adapter panel. The eight LC/UPC connectors plug into blue flat-polish LC ports on duplex optics or patch panels. Push each connector until it clicks, keep APC to APC and UPC to UPC, and confirm the MPO port is pinned — this cable is female and needs pins on the opposing side.

Which breakout should I choose, single mode OS2 or multimode OM4?

Choose this OS2 breakout when the parallel port is single mode (PSM4 class), when links leave the data hall, or when future speeds may outgrow multimode reach. Choose an OM4 breakout such as FB124-4CXX when the electronics are SR4-class multimode and runs stay short — the optics typically cost less. The fiber type must match the transceivers at both ends of the link.