This part is a kind of semiconductor called 2N6121.

Function of this product has NPN PLASTIC POWER TRANSISTOR.

Manufacturers : CDIL

Image and pinout :

Some of the text within the PDF file :

Continental Device India Limited An ISO/TS 16949, ISO 9001 and ISO 14001 Certified Company TO-220 Plastic Package 2N6121, 2N6122, 2N6123 2N6124, 2N6125, 2N6126 2N6121, 6122, 6123 NPN PLASTIC POWER TRANSISTORS 2N6124, 6125, 6126 PNP PLASTIC POWER TRANSISTORS Medium Power Linear and Switching Applications PIN CONFIGURATION 1. BASE 2. COLLECTOR 3. EMITTER 4. COLLECTOR 4 N LH BF C E A OO 12 3 K D G J M All diminsions in mm. 1 2 3 DIM MIN . MAX. A 14.42 16.51 B 9.63 10.67 C 3.56 4.83 D 0.90 E 1.15 1.40 F 3.75 3.88 G 2.29 2.79 H 2.54 3.43 J 0.56 K 12.70 14.73 L 2.80 4.07 M 2.03 2.92 N 31.24 O DEG 7 ABSOLUTE MAXIMUM RATINGS Collector-base voltage (open emitter) Collector-emitter voltage (open base) Collector current Total power dissipation up to TC = 25°C Junction temperature Col [ ... ]

2N6121 PDF Datasheet Download