"MATERIAL:STEEL,FORGING,ALLOY 4150GRADE D,SPEC MIL-S-46172;HEAT TREATMENT:QUENCH AND TEMPER ROCKWELL C30-36;SURFACE HARDEN INDICATED AREAS IN ACCORDANCE WITH SPEC MIL-S-12515 TO 58 -62 RC SURFACE HARDNESS,HAS THREE ARMS EQUALLY SPACED WITHIN0.002,WIDTH OF EA. ARM IS MIN. 0.460 IN. AND MAX. 0.464 IN."