This is a 10x3.85 Slo-Flyer "tractor" (not a "pusher") airplane propeller. This prop produces a lot of torque even at low speeds. FEATURES: Computer-optimized design gives these props a thinner profile and more "bite" with less noise. Lightweight molded nylon construction reduces rotating mass for higher output and longer life. Reinforcing carbon fibers help maintain true, constant pitch at any rpm. Slo-Flyer propellers work well with Electric powered Park Flyer-type aircraft. INCLUDES: One carbon-reinforced nylon propeller One set of small shaft locating rings One locating ring instruction sheet REQUIRES: ALL props require balancing (use TOPQ5700) May need prop reamer, use GPMQ5006 (SAE) or GPMQ5007 (Metric) SPECS: Length: 10" Pitch: 3.85 COMMENTS: Slo-Flyer props are Not designed for Glow enginesAPCPart APCLP10038SF