Handlebar Lever Assemblies for Clutch & Brake Levers. This is the part that clamps to your handlebars with a clutch or brake lever attached. Some have the threaded screw holes for mirrors (known as the mirror boss) and some are universal which means they can be used on any handlebar so long as the bars diameter is 7/8" or as otherwise stated and that your cable has same nipple on the end to fit the hole as shown by the image. 
Can't Find it? Browse For Your Model Top Left of This Page or Search Using The Search Box