You are viewing a new set of OES swingarm spools for the 1998-2020 Yamaha YZFR1 (includes R1M and R1S). These spools have extra material on them to function as sliders to help protect your swingarm in a crash. They are CNC machined from black Delrin and measure 1-1/2 inches in diameter and 1-1/2 inches long. Stainless steel 6mm mounting screws and washers are included. The grooves on these where your swingarm stand makes contact are deep so the engagement is solid, which makes it less likely for your bike to fall off the spools.