The QSFP40GLR4ES is a Dell EMC QSFP-40G-LR4 compatible fiber transceiver module that has been designed, programmed and tested to work with Dell EMC brand switches and routers. It delivers dependable 40 GbE connectivity over fiber cable, for 40GBase-LR4 compliant networks, with a maximum distance of up to 10 km (6.2 mi). This QSFP+ 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.