This is a Master Airscrew 11x6 Nylon Prop for Electric Motors. FEATURES: Designed exclusively for Electric flight. Made of "glass-filled nylon for durability. For direct drive or gearbox use Blades are wide and thin to provide the flex needed for hard landings Undercambered blades give great thrust and pull for superior perfor- mance. Bore size is a uniform 1/4" INCLUDES: One 11x6 Nylon Propeller and six spacers for Electric Motors. SPECS: Hole Diameter: 1/4" (6.3mm) Propeller Diameter: 11" Propeller Pitch: 6" COMMENTS: These props are only for Electric motors. rda7/26/06 ir/jxs