The SFP-Port 1000BASE-BX (WDM, TX:1310nm) mini-GBIC module - 20km (Part number: MGB-LA20) from Planet is a Transceivers Fiber & Copper. A transceiver is a combination of transmitter and receiver used in fiber optical systems, which are combined and share a common circuitry or a single housing. Fiber optic transceivers are classified into various types to meet diversified requirements.