The shimano m647 spd mountain bike pedals have been kitted out with loads of strength and durability featrues that makes it ideal for downhill racing and bmx ridingstarting off with a heavy duty aluminium body with a high impact resin composite cage to ensure it can handle even the most extreme riding without cracking under pressure the shimano mtb pedal also uses a cr mo spindle with a sealed bearing cartridge axle to ensure that the pedal always turns smoothly and is less prone to pickin