This is the replacement Prop Adapter for the 50mm Diameter Great Planes RimFire Brushless Motors. FEATURES: Aluminum construction, Silver in color Replaces a worn or damaged prop adapter INCLUDES: One Prop Adapter One Prop Washer One Prop Nut REQUIRES: Four 3x10mm Cap Head Screws to mount the adapter to the motor can (salvage screws from old prop adapter) SPECS: Length: 1.80" (45.6mm) overall 1.41" (36mm) shaft only Diameter: .37" (9.5mm) Thread: 3/8 x 24 kpm02/20/2007 ir/jxs