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-LH-SM fully complies with the IEEE 802.3z 1000BaseLX standard. However, their higher optical quality allows them to reach 10 km over single-mode fiber (SMF) versus the 5 km specified in the standard.

This device is currently ON SALE