5steel; 10.750 in. Major dia; 10.375 in. Minor dia; 52 gear teeth; 4.625 in. Od hub; 3.912 in. Id hub; hub splined internal 36 involute; 3 unthd bolt holes; 0.750 in. Dia; 7.750 in. Bolt circle; 3 thd holes 0.500-12 uns; 5.625 in. Diameter bolt circle