AKA inserts are the original closed cell insert that started the revolution in the tire industry. Now copied by every tire manufacture, AKA inserts are ground into shape ensuring consistent concentricity and balance in every insert. AKA inserts are the longest lasting inserts in the industry. Don't be afraid to use them in several sets of tires. Also, don't worry about washing your tires and destroying the insert. AKA closed cell inserts are not harmed by water like urethane inserts. Go with the original. Go with the best.