APC Thin Electric 4.1x4.1 Prop
APC Electric Speed 400 Series props offer high efficiency and great value for your electric powered models. These props are designed for high speed operation on Pylon Racers, Hot-liners, Flying wings and other similar applications. The center hole of the prop is designed to accept a reducing bushing to fit your propeller shaft. Included with the prop are 2 bushings to fit 5mm and 3/16 inch prop shafts.
According to the widely accepted Maximum RPM formula of 190,000/D for APC E-Series props, the 4.1x4.1 prop should not be used over 46,341 RPM.