Our armored single-mode line comes in two fiber counts: 2-fiber (duplex) and 4-fiber. The right choice depends on how many links you are lighting up — and whether you want spares in the ground for free.
What a fiber count actually means
A standard duplex Ethernet link uses exactly two fibers: one transmitting, one receiving. That is why patch cords are sold as “duplex”. A 2-fiber armored cable carries one duplex link. A 4-fiber cable carries two duplex pairs in the same armored jacket.
When 2-fiber is right
- You are connecting exactly one device pair: switch-to-switch, ONT-to-router, camera-to-NVR uplink.
- You want the lightest, thinnest cable for the run (duplex armored cable is smaller OD and easier to pull).
- Budget matters and there is no second link planned.
When 4-fiber earns its cost
- Redundancy: light up one pair today, keep the second pair as a cold spare. If a connector is ever damaged in the field, you re-terminate nothing — you just move to the spare pair.
- Two links, one pull: pulling cable through conduit or burying it is most of the labor. A 4-fiber trunk does two duplex jobs with one installation.
- Future growth: the second pair is there when bandwidth or device count grows.
Our 4-fiber OS2 trunk breaks out to four numbered LC/UPC connectors per end (two duplex pairs, labeled 1–4), while the 2-fiber OS2 duplex uses a single Uniboot LC per end — two fibers in one compact housing for dense panels.
Rule of thumb: if you will ever need a second link on the same route, buy 4-fiber once instead of installing twice.