This is a 18x8W One-Piece Composite Propeller from Advanced Precision Composites FEATURES: Gray composite one-piece construction Comes in a bag attached to a header card INCLUDES: One composite propeller REQUIRES: ALL props require balancing, this is VERY important, use TOPQ5700. May need prop reamer, use GPMQ5005 (SAE) or GPMQ5007 (Metric) SPECS: Diameter: 18" Pitch: 8 Hub inner diameter: 0.30" cdh8/26/03 ir/jxs