StarTech.com Cisco SFP-10G-BX-U-40 Compatible SFP+ Module - 10GBASE-BX - 10 GbE Gigabit Ethernet BiDi Fiber (SMF)

Product Overview

AI-generated summary

For £26 ex-VAT this is the kind of SFP+ you grab when you’re keeping existing 10GbE kit running on a budget. StarTech’s “compatible” modules are usually fine in normal, well-matched lab/data-hall conditions, especially when you’re replacing a failed optic in a like-for-like link and you don’t want to pay Cisco/Finnish-brand tax. If you’re running short-ish runs on single-mode with the correct BiDi (TX/RX on different directions) setup, and you’ve already confirmed your switch supports that optics type, it can be a sensible way to restore uptime without overthinking it.

That said, I wouldn’t buy it blindly if your network is finicky or you’re mixing vendors/models: some switches are pickier about module vendor/DOM signalling and you can get “works at first, then flaps” headaches. Also, since it’s BiDi, make sure you’ve got the right fibre pair and polarity plan—getting that wrong is a classic way to waste time. In short: buy it if you’re doing a straightforward replacement and you know your gear and fibre topology; avoid it if you’re trying to use it as a general-purpose fix across unknown hardware or long/temperature-stressed links.