The Cisco SFP-10G-ZR is a multirate 10GBASE-ZR, 10GBASE-ZW and OTU2/OTU2e module. It supports link lengths of up to about 80 kilometers on standard single-mode fiber (SMF, G.652). This interface is not specified as part of the 10 Gigabit Ethernet standard and is instead built according to Cisco specifications.