These cutting edge tensioners are CNC’d from 6061 T6 aluminum and feature a revolutionary single screw adjustment system. Unlike some chain tensioners, the Solo’s use a proprietary 2.5mm single adjusting screw that operates independent of a “C” ring or Clip device, allowing for smooth and reliable adjustment of your drive train - every time. With only two moving parts, these are one of the most reliable and convenient chain tensioning devices on the market. In addition, our new tensioners come equipped with axle shims to accommodate M6 Allen bolts commonly found on mini and expert size wheel sets, eliminating any space between the axle and tensioner to ensure consistent and accurate adjustment. The ultimate marriage of form and function, everything you have come to expect from Crupi.  Sold as a set of 2.