Shimanos M520 pedals feature a chrome-moly sealed spindle and a low-maintenance sealed bearing cartridge axle. The compact body design with open binding provides easy entry, and tension settings are customizable. Designed to provide excellent mud and debris shedding ability. Shimanos SPD is a system that performs whether youre on or off the bike. It makes pedaling more efficient with a wide variety of shoe and pedal styles and the recess cleat makes walking more comfortable. You can pedal with greater efficiency, stability and comfort with the SPD system. Shimanos Alivio M3100 series delivers a low-profile set designed to let you ride aggressively with fewer interruptions.