The image illustrates a kit of 4 inserts for 2 size handlebars, which is what originally comes with the Acerbis handguards. THIS IS NOT WHAT YOU WILL GET!!!! I ordered, thinking that I would receive this kit, but only received 1 insert instead. Now, I gotta waste ANOTHER $24 shipping and handling just to get the other one .. sheesh!
I don't have the exact ID or OD of these inserts, but I do know this kit will include two sets of quills that should cover all aluminum handlebar ID (inside diameter). These are to be used w/ the rally brush handguard.