It is stated in the Adventurer Owners manual under Loading your camper on your truck. I have been using Fastguns on all 4 corners. However one of the Fastguns appears to be having a problem. The spring loaded barrel appears to be pushed up towards the top. They were part of the deal when we bought our old camper so I was using them. However if one has broken. Then I thought I might use turnbuckles on the rear. Not to question the manufacter. But a little give with the Fastguns one would think would be a good thing.That was why I was wondering what your opinion was.