The description :

• The transistor is an electronic component with three active electrodes which is used in most electronic circuits, it allows to control a current or a voltage on the output electrode This is a bipolar junction transistor named BD135.
• A bipolar transistor is a type of transistor that uses both electrons and holes as charge carriers.

It has 3 terminals, which are:

• Transmitter.
• Collector.
• Based.

Specifications:

• Type: bipolar NPN
• Model #: BD135
• Current: 1A.
• Voltage: 45 V.
• Dissipated power: 12.5W
• Junction operating temperature range: -55 to 150C 0
• Technical sheet :https://www.electronicaembajadores.com/datos/pdf1/sm/smtr/bd135_37_39.pdf