I was trying to find something to keep the shift boot up against the shift ****. Hated the slop. I have a Pro 5.0 shifter. Nothing was available so I made my own from a Honda dirt bike axle nut that measures M16x1.5 and some 3/4 OD PVC pipe with a PVC coupler to make the sidewall thicker.

I glued the coupler on to the pipe then cut it to the size I wanted. About 1/4" thick. Then ran a 41/64 drill bit down the middle to auger it out to an internal diameter of 5/8 (16mm). Painted it with SEM Landau black.

I flipped the nut upside down so the flange was pointing up, then threaded it down so it would be under the top of the leather shift boot. Then slid the PVC ring down to pinch the leather between the nut and the PVC ring, and finally installed the shift **** which tightens it all together and keeps the boot up against the bottom of the **** like I wanted.

My boot is in terrible shape so I'm waiting for a leather one from Redline but the ring is doing what I wanted it to.