I found what looks to be a stronger than average coupler lock - the Proven Industries Coupler Lock model 2178. It also secures the safety chains, if you want.
unlike some other web sites that sell it for $195!
It looks as if it may be a stronger design than the (somewhat similar) MegaHitch Lock.
The manufacturer (Proven Industries) asked me to email them a photo of the coupler to make sure they send me the right variant of the 2178.
1) Is anyone here using it on a 21 Escape? (we get ours in 2017)
2) Is the coupler on a 19 Escape (photo attached, that I found here on this forum) identical to the coupler on a 21 Escape?
3) any other similar beefy coupler locks other than these two? (I have been doing web searches)
4) I looked thru many threads here... I could not find any (more close up) pics of an Escape coupler... bonus points if anyone here wants to upload better pic(s) - thanks!