sturdiest device that you cant get out of easy

I’ve been sticking with total denial in resin. The main issue is that it pinches and causes sores, but I appreciate how difficult it is to remove if I choose to (which I don’t). What I need is the sensation of truly being locked up—especially knowing I couldn’t get back into it easily once out. My wife prefers something she can pull me around by instead. Are there metal options that resist escape? No Prince Alberts or piercings please.