Plastic bat. Revolutionary injection molded bats can't warp & will never wear out. Pin holes don't come through to the throwing surface. so pot bottoms wont be marked. Easy lift rimsmakes it easy to get your fingers under the edge for easy removal. Adapts to both 9" & 10" center to center pin systems. A unique design allows a perfect fit without jamming for all wheels which use sytems with 3/8" diameter pins. No expensive adapter required.