This is the Cisco industry standard SFP, which stands for Small Form-Factor Pluggable (part number GLC-LH-SM).  This device plugs into a Gigabit Ethernet port on a variety of Cisco devices (Router, Switches, etc) and is hot-swappable.  The Cisco GLC-T is a 1000BASE-T SFP Transceiver Module for Category 5 copper wire.

This device is currently ON SALE