Park tool dummy hubalso called a sleeping hub the dh 1 slides into rear dropouts and replaces the rear wheel for chain cleaning and transport the dh 1 works with all derailleurs and 18 chains the unique design allows the bike to be shifted and works with open dropout and thru axle frames up to 12mm features perfect for drivetrain cleaning or transport works with all derailleurs and 18 chains works with open dropout and thru axle frames up to 12mmbuypark tool workshopfrom chain reaction