Our chainring is perfect for MTB use. billet aluminium( 7075-T6 aviation aluminum) machined with CNC machine, coated with a beautiful anodized protective film to prevent corrosion, and available in red and black colors. the narrow wide 34 teeth toothing is specially designed to retain the chain. this chainring is very light only 87gr instead of 540gr for the original steel chainring. If you want to improve BBSHD motor performance, the chainring could be for you.