The SFP-10GB-BX-D-20-ST is a MSA Compliant downstream fiber SFP+ transceiver which pairs with StarTech.com\'s SFP-10GB-BX-U-20-ST. They are designed, programmed and tested to work with 10GBase-BX compatible MSA switches and routers. The SFP+ transceiver module supports a maximum distance of up to 20 km (12.4 mi) and delivers dependable 10 GbE connectivity over fiber cabling. This SFP+ fiber module is hot-swappable, making upgrades and replacements seamless by minimizing network disruptions. StarTech.com offers a wide variety of SFP+ modules and direct-attach SFP+ Cables, providing the convenience and reliability you need to ensure dependable network performance.