Review on 18mm Bolt-Style Top Dead 🔧 Center Stop by COMP Cams 4792 by Michael Boyd

I accidentally bought 18mm, I found 14mm on the spot, seems to work, I used it on BBC, spark plugs in this engine are 'flat' in comparison to a high angle to keep the stopper from screwing all the way in and touching the plunger, but I took a chunk of the entire thread and it worked fine. Twists, although I'm not sure if it matters, this part was still a good start for not doing it yourself.