This is 45PCS SOCKET SET(1/4),Material can be CR-V or 45# carbon steel. 6PCS-1/4”DR.SOCKETS :5,6,7,8 ... ,9,10MM 1PCS-1/4”(M)*3/8”(F)ADAPTOR 12PCS ... -3/8”DR.SOCKETS:7,8,9,10,11,12,13,14,15 ... ,20,25,27,30,40,FD4,5,6,7,HW3,4,5,6MM 1PC-3/8”DR.SPARK PLUG SOCKET:16MM ...