These inserts are for the JConcepts Rupture or FYR tires 4.75 2.2 1.5 on 30mm 2.2 wheels, (Very common in the 2.2 size) wheels these will require cutting the stock foams a lot, you will then tune the foams to get the stiffness you want. They provide sidewall support yet compress for those difficult pressure points we all get into.
