The ultimate solution for Shimano and other 64/104BCD cranks. If you have ever thought about running 1x9/10/11 and wondered how to solve chain retention, this is an answer. Its specially designed wide-narrow tooth profile keeps the chain really snug, allowing you to leave your chainkeeper in the garage. Always use a new chain with a new chainring 64BCD: 26T (34g), 28T (40g), 30T (44g)