Mouting Type: 4 Bolt Std - 44.40 [1.748] Dia. 375-16 Unc-2b Mounting Holes On 82.55 [3.250] Dia. Output Shaft: 25.4 [1.00] Dia. 250-20 Unc-2b Hole In Shaft End. 500-14 Nptf Dryseal Pipe Thread Ports.