The SFP10GBX40DS is a Dell EMC SFP-10G-BX40-D compatible downstream fiber SFP transceiver which pairs with Star Tech.com's SFP10GBX40US. They are designed, programmed & tested to work with 10 G Base-BX40 compatible Dell EMC switches & routers. The SFP+ transceiver module supports a maximum distance of up to 40 km (24.8 mi) & delivers dependable 10 Gb E connectivity over fiber cabling. This SFP+ fiber module is hot-swappable, making upgrades & replacements seamless by minimizing network disruptions. Star Tech.com offers a wide variety of SFP modules & direct-attach SFP Cables, providing the convenience & reliability you need to ensure dependable network performance.