This adapter fits GM 1 ton tie rod ends and is used for OTK flips (over the knuckle). You need to ream your knuckle hole to 7/8″ to use this adapter. You can use a standard drill bit, but it makes the job FAR harder, we suggest using the reamer to make quick work of it. The appropriate reamer can be found here 7/8″ Reamer for TRE Flip Kits
Does NOT fit high angle TREs like the 2026R.