The ACME 3223 is a CNC machined 4 blade Nibral propeller designed for high performance wake and ski boats. With a 15.50″ diameter and 16.75″ pitch, it generates strong acceleration and smooth ride quality. Diameter: 15.50″ Pitch: 16.75″ Cup: .135″ Hub Length: 03.125″ Bore: 1.25″ Blades: 4 Rotation: Left