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 an IGBT transistor.
• An IGBT (Insulated Gate Bipolar Transistors) consists of a voltage controlled MOSFET followed by a high current transistor

It has 3 terminals, which are:

• Transmitter.
• Collector.
• Based.

Specifications:

• Type: IGBT
• Model #: 25N120
• Enclosure: TO-3
• Nominal current: 50 A.
• Nominal voltage: 1200 V.
• Max power: 349 W
• Junction operating temperature range: -55 to 150C 0
• Technical sheet :https://www.onsemi.com/pdf/datasheet/ngtb25n120flw-d.pdf