2n6655.pdf datasheet:

2N6655Dimensions in mm (inches). Bipolar NPN Device in a Hermetically sealed TO3 25.15 (0.99)6.35 (0.25) 26.67 (1.05)9.15 (0.36)Metal Package. 10.67 (0.42)11.18 (0.44) 1.52 (0.06)3.43 (0.135)1 2 Bipolar NPN Device. 3VCEO = 400V (case)3.84 (0.151)4.09 (0.161)7.92 (0.312) IC = 20A 12.70 (0.50) All Semelab hermetically sealed products can be processed in accordance with the requirements of BS, CECC and JAN, JANTX, JANTXV and JANS specifications. TO3 (TO204AA) PINOUTS 1 Base 2 Emitter Case - Collector Parameter Test Conditions Min. Typ. Max. UnitsVCEO* 400 VIC(CONT) 20 AhFE @ 15/10 (VCE / IC) 10 -ft 75M HzPD 150 W* Maximum Working Voltage This is a shortform datasheet. For a full datasheet please contact sales@semelab.co.uk.Semelab Plc reserves the right to change test conditions, parameter limits and package