Heavy-Duty thick wall tube tool from Jims-USA. Extra long two piece design, inner collar will retain wrench to nut for safer service work. Used to install or remove the 1 7/8" hex nut that secures the final drive sprocket or pulley on the transmission main shaft on all Big Twins from 1936 thru 2006, except 2006 Dyna. Use with 1/2" drive ratchet.