Special superb extra strong timing chain with very limited stretch to keep your timing correct to fit any A series engine using a single row chain. Worth every extra pound cost for longevity and quietness.
The twin row chain duplex gear set introduced on Cooper S engines uses 2H4905EVO. Check your timing gears for wear. Please note that the cam gear with the tensioner rings was superseded by the plain gear which is the only type available. This chain works superbly on A plus tensioner type engines even if tuned and is worth the extra expense for longevity.