BIKE ½” x 1/8” 42 TEETH 5 BOLT ALLOY CHAINRING 130mm BCD. Very low price for this 42 teeth 5 bolt chainring ½ x 1/8 teeth with a BCD of 130mm. These could be used on fixies, bmx or standard bikes in fact any single speed or internal hub geared bike that use 1/8” chain.