The sram x01 xsync 104bcd 11 speed chain ring are the designed to replace your old chain rings on your x01 cranks featuring a 104 mm bolt circle diameter it is the perfect replacement for your old and worn out rings the build design on the sram x01 x sync chain rings is incredibly sturdy making them perfect for the heavy mountain bike riding that the x01 range has been designed for the chain rings are also super light weight when compared to their alternatives when fitting t