Lost a pin on the tow bar. Don't use these pins!!

In both cases, both my tow bar pins were just plain missing. Again, the first time I though, wow, maybe I had it backwards but since I have farm machinery and such, I am careful of how I hook things up. Second time, no way. Something gave with those pins and they were gone. Just won't use them again. No chance of removal by evil people or anything either. This was a direct stop/go. No stopping anywhere.