This part is a kind of semiconductor called 7809.

Function of this product has 3-terminal 1A positive voltage regulator.

Manufacturers : SEMTECH

Image and pinout :

Some of the text within the PDF file :

7809 3-terminal 1 A positive voltage regulator Features • Output Current up to 1 A • Thermal Overload Protection • Short Circuit Protection • Output Transistor Safe Operating Area Protection Absolute Maximum Ratings (Ta = 25 OC) Parameter Input Voltage Thermal Resistance Junction-Cases Thermal Resistance Junction-Air Operating Temperature Range Storage Temperature Range TO-220 Plastic Package Symbol VI RθJC RθJA TOPR TS Value 35 5 65 0 to + 125 - 65 to + 150 Unit V OC/W OC/W OC OC Electrical Characteristics (0 OC < TJ < 125 OC, IO = 500 mA, VI = 15 V, CI = 0.33 µF, CO = 0.1 µF, unless otherwise specified) Parameter Symbol Conditions Min. Typ. Max. Unit TJ = 25 OC 8.65 9 9.35 Output Voltage VO 5 mA  IO  1 A, PO  15 W VI = 11.5 V to 24 V 8.6 9 9.4 V Li [ ... ]

7809 PDF Datasheet Download