This sleeve is used when doing a steering linkage flip on a JK Wrangler 2007+ all models. The steering drag link from the steering gear to the passenger knuckle normally enters the knuckle from the bottom side. With this sleeve the hole is enlarged to 13/16" or 0.8125" and using the new heavy duty drag link from TeraFlex the drag link is installed from the top. The inside taper matches the stock JK taper which is a 7.116 degree angle. Not the same as the TJ taper.
Note; this is part of a complete flip kit which addresses the proper track bar drag link geometry. Don't try changing the draglink without relocating the track bar mounting location or you will have some dangerous bump steer problems.