The Cisco FET-40G QSFP module is a fabric extender transceiver module used to connect to fabric links (links between the fabric extender switch and the parent switch). The interconnect will work over parallel multimode fiber across distances of up to 100 m and 150 m, respectively, on laser-optimized OM3 and OM4 multimode fiber cables. This module can be used for native 40G optical links over 12-fiber ribbon cables with MPO/MTP connectors or in 4 x 10G mode with parallel to duplex fiber breakout cables for connectivity to four FET-10G interfaces.