In order to change the Shimano freehub body to an XDR freehub body, the user will need to use two 17mm cone spanners. Loosen the non-drive side end cap in the anti-clockwise direction and take it away by hand. Grab the hub shell, twist and pull the freehub body and axle so as to remove. Strike the axle on the surface to remove the internals. Now insert the double spacer barrel in the XDR freehub body while making certain that the larger lip of the barrel faces the XDR freehub body. The barrel should be flush to the XDR freehub body. Insert the spacer barrel, leaf spring with the leaf springs facing the hub shell, the ratchet ring on the freehub body. Take the free hub-body and insert it back to the hub shell, use the cone spanners to tighten the non-drive side end cap, Congratulations XDR freehub body is now installed.