This part is a kind of semiconductor called 2N6395.
Function of this product has (2N6395 - 2N6398) SILICON CONTROLLED RECTIFIERS.
Manufacturers : Dc Components
Image and pinout :

Some of the text within the PDF file :
DC COMPONENTS CO., LTD. R DISCRETE SEMICONDUCTORS 2N6395 THRU 2N6398 TECHNICAL SPECIFICATIONS OF SILICON CONTROLLED RECTIFIERS VOLTAGE RANGE - 100 to 600 Volts CURRENT - 12 Amperes Description * Driven directly with IC and MOS device * Feature proprietary, void-free glass passivated chips * Available in voltage ratings from 100 to 600 volts * Non-sensitive gate trigger current * Designed for high volume, line-powered control application in relay lamp drivers, small motor controls, gate drivers for large thyristors TO-220AB .185(4.70) .173(4.40) .055(1.39) .045(1.15) .295(7.49) .220(5.58) Pinning 1 = Cathode, 2 = Anode, 3 = Gate .151 Typ (3.83) .405(10.28) .380(9.66) Absolute Maximum Ratings(TA=25oC) Characteristic Peak Repetitive Off-State Voltage and Reverse Voltage 2N6395 2N6396 [ ... ]
2N6395 PDF Datasheet Download
