the long skinny ones do not work because the latch recesses. I want to lock it on the ball when towing. most round locks are to thick. I just thought if anyone has a similar unit to mine they could suggest what they use. "downtheroad" I have tried your kind but have not found one that is skinny enough for the hole.
I have a 2012 Rockwood Roo 23SS. I have tried different coupler locks and none fit. The hole is small and when in lock position, it is recessed. What do you all use? We have been using a zip tie but only doing short trips. I have a 5 hour trip coming up for the 4th and want something more secure. HELP!