This is a 3-Bladed 6x4 (15x10cm) Pusher Prop by Master Airscrew. FEATURES: NACA Airfoils True Pitch Accurately Balanced Greater Thrust at Lower RPM Glass Filled Nylon INCLUDES: One Propeller REQUIRES: Hub Drilled for Engine Size SPECS: Pitch: 4 Diameter: 6" rmb 9-07-06 ir/jxs