Amarine-made 5-Spoke 13-1/2 Inch Destroyer Style Stainless Boat Steering Wheel with M Size Knob - 9310SRF1 5 spoke stainless steel 3/4" shaft with (1) notch tapered keyway 13 1/2" diameter x 3 3/8" deep Polished to a bright mirror finish, Control Knob included Includes black plastic center cap.