0.1250" FIRST0.1250" first hole diameter 4.3125" 4.3125" overall length all diameters to be concentric within 0.001 tir, 4 straight internal grooves opened on both ends 90 deg apart 0.0625 in. dp by 0.1875 wide, 1annular external groove 0.5313 in. from left end 0.1250 in. dp by 0.5000 in. wide, 4 hole s 90 deg apart 0.625 in. from left end intersect internal 17c solid, plain, no outside flanges