StarTech.com Arista Networks QSFP-40G-XSR4 Compatible QSFP+ Module - 40GBASE-SR4 - 40GbE Multimode Fiber MMF Optic Transceiver - 40GE Gigabit Ethernet QSFP+ - MPO 400m - 850nm - DDM

Product Overview

AI-generated summary

For £37.85 ex-VAT, this is the kind of QSFP+ optics you buy when you need *working links now* and you’re confident your switch supports this exact type of transceiver. The “Arista compatible” angle is usually fine for straightforward, vendor-qualified optics setups, and the fact it has DDM is genuinely useful—if you’re troubleshooting flaky fibre links, being able to read power/temperature without guessing saves time. For short-to-medium multimode runs on an MPO-backed patching setup, it can be great value.

That said, I wouldn’t treat it as a “universal always works” purchase. If your Arista platform is picky about optics compatibility (or you’re in an environment with stricter transceiver authentication), you may get warnings, reduced link stability, or outright non-recognition—so it’s worth checking your switch’s optics compatibility list or testing one module before you buy in bulk. Also, it’s aimed at **40G multimode** use cases; if you’re trying to move beyond the stated reach or you’re on single-mode cabling, you’ll just be paying for the wrong thing. If you’ve got the right multimode fibre and you can verify compatibility, it’s a sensible, budget-friendly pick; if not, spend a bit more on optics you know will behave.