BUY BUX21 https://www.utsource.net/itm/p/915546.html
SILICON N-P-N SWITCHING TRANSISTOR
Package: TO-3 Manufacturer: MOT Description: BUX21 is a NPN silicon power transistor manufactured by MOT. It is designed for use in general purpose amplifier and switching applications. Features: - High current gain - Low collector-emitter saturation voltage - Low collector-emitter leakage current - High DC current gain - Low noise Applications: - Audio amplifiers - Switching applications - General purpose amplifiers - Power supplies - Motor control circuits (For reference only)