Single Mode Single (Smf) Fiber Sfp (Small Form-Factor Pluggable) Tx (Trans)1310 Nm / Rx (Re Ceive) 1550Nm , Sfp-Baset 1G, Supports 15 To 20 Km Distance, Interface-Lc, Digital Optical Monitoring (Do M) Support, & As Per Attached Specs. [Blue Unit Type T1310/R1550, Yellow Unit Type T1550/R1310] [ Warra Nty Period: 12 Months After The Date Of Delivery ] ]