ACCURATELY VALVES:TheValve Hand Lapping Grinding Tool Kit 2-Piece Set-Dual-End Suction Cup Lap Stick,1-1/8 inch,1-3/8 inch,5/8 inch,3/16 inch Inch helps you properly match valve seats during an engine top-end rebuild; These tools include dual ends with oil and UV-resistant synthetic rubber cups that help you put the finishing touches on your tune-upVARIOUS APPLICATIONS:Suitable for any clean,flat surface of a lawn mower,chainsaw,or small or large engine car or other vehicle with 5/8-inch,13/16-inch,1-1/18-inch,and 1-3/8-inch (1.6cm,2.1cm,2.9cm,3.5cm) valves; 8.9-inch and 8.3-inch (22.6cm and 21.1cm) overall lengths make these tools useful for even installing and removing recessed fixtures or hard-to-reach mini-flood light bulbsGRIP COMFORTABLY:6.75-inch (17.1cm) long handles for ultimate control,less user fatigue,and more productivity; 8.9-inch and 8.3-inch (22.6cm and 21.1cm) overall lengthsEASY TO USE:Clean all carbon deposits off valve and wipe down each valve,install valve in valve guide,press correct size suction cup firmly onto head of valve,and lightly spin tool handle between palms of your hand (as if trying to start a fire) until a suitable finish is obtained; We recommend placing valve lapping/grinding compound (not included) on valve or valve surface (keep compound off the top surface of the valve to ensure proper suction)Color:yellow+blackMaterial:plastic+woodPackage Contents:2* valve grinderOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.