This is a 9.5x4.5 airplane propeller. It is a "tractor" (not a "pusher") prop. / / 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. / "C2" design. / / INCLUDES: One carbon-reinforced NYLON propeller / / REQUIRES: ALL props require balancing, this is VERY important, use TOPQ5700. / May need prop reamer, use GPMQ5005 (SAE) or FOXQ1520 (Metric) / / SPECS: Length: 9.5" Pitch: 4.5 / Thickness at hub: 1/2" Hole diameter: 1/4" / 3-25-98/eke / ir/le