C/o transistor, p/n 135622-03; heat sink, p/n 141083-21, material 5052, h-32 aluminum alloy, per qq-a-318, 0.0611 to 0.0681 in. Thk; heat sink dimensions1.800 in. Lg; 0.750 in. W; 2 holes, 1 ea end 0.203 to 0.209 in. Diameter w/centerto center 1.300 in. Lg; 3 holes in center for mounting transistor 0.086 to 0.092 in. Dia, center to on 2 holes 0.282 in., 3rd hole 0.141 in. Below center between other 2 holes