Cisco 40GBASE Quad Small Form-Factor Pluggable (QSFP+) Modules - QSFP-40G-SR-BD= QSFP40G BiDi Short-reach Transceiver 150 m - QSFP-40G-SR4-S= 40GBASE-SR4 QSFP Trnscvr Module, MPO Conn, Enterprise-Class 150 m - QSFP-40G-SR4= 40GBASE-SR4 QSFP Transceiver Module with MPO Connector 150 m - QSFP-40G-CSR4= QSFP 4x10GBASE-SR Transceiver Module, MPO, 400 m - WSP-Q40GLR4L= QSFP 40G Ethernet - LR4 Lite, LC, 2KM REMANUFACTURED 2 km - QSFP-40G-LR4-S= QSFP 40GBASE-LR4 Trnscvr Mod, LC, 10km, Enterprise-Class 10 km - QSFP-40G-LR4= QSFP 40GBASE-LR4 OTN Transceiver, LC, 10KM - QSFP-40G-ER4= QSFP 40GBASE-ER4 Transceiver Module, LC, 40KM Chúc các bạn có lựa chọn hợp lý!