The rohloff speedhub chain tensioner is a spring loaded device that maintains chain tension in a single driveline application it can be used with the rohloff speedhub 50014 when horizontal adjustment of the hub is unattainable or in rear suspension applications where the distance between the bottom bracket and the rear axle change throughout the range of travel the rohloff chain tensioner is an excellent choice for any conversion to a single driveline system ie speedhub 50014 or singlespe