StarTech.com Cisco QSFP-40GE-LR4 Compatible QSFP+ Module, 40GBASE-LR4, 40GbE Single Mode (SMF) Fiber SMF Optic Transceiver, 40GE Gigabit Ethernet QSFP+ LC 10km, 1270nm to 1330nm, DDM - Lifetime Warranty (QSFP-40GE-LR4-ST) - QSFP+ transceiver module (equivalent to: Cisco QSFP-40GE-LR4) - 40GbE - 40GBase-LR4 - LC single-mode - up to 10 km - 1270-1330 nm