It is an LM317T Adjustable Voltage Regulator. They are designed to supply more than 1.5 A of load current with an output voltage adjustable over a 1.2 to 37 V range. The nominal output voltage is selected by means of a resistive divider. This makes the device exceptionally easy to use and thereby eliminating the need for stocking of many fixed regulators.
Package Includes:
1 x Voltage Regulator LM 317