Order Includes: 4x Plugs. Compatible with Yamaha models: YZFR1 2004-2008. Part Number: 90338-23004-00. Dimensions and Measurements: Inner Diameter: 24.4 mm / 0.96 ", Outer Diameter: 31.3 mm / 1.23 ", Width: 10.7 mm / 0.42 ". We strongly suggest comparing the posted picture to the unit(s) that needs to be replaced..
