I know this is going to be a really stupid mistake but i would like for others to learn if they dont already know. We have a 2003 Ford F250 and a 1995 Coachman 28' 5th wheel. Went on our first trip and backed in to the spot. I got out and set the boards up to level the trailer. Put the trailer up on the boards chocked the wheels with the Yellow ones you can buy at Walmart. Cranked up the camper off the hitch. Got out and pulled the release and the camper started to role back It droped about 2" on the bed of my truck and luckly it stoped on the tailgate not much damage done. Must because it is Ford Tough.... After my girlfriends heart got under control and i changed my underware I fixed the problem and went on. As we was camping i looked around and saw come of the campers have the wheel chockes that go between the two tires. I did some resource on the internet and most was running around 50 to 60 dollors apiece and most said you should get a pair. I found a set on Ebay that you get a pair for around 70.00. A lot i saw on the internet you had to use a wrench or untighten a bolt everytime. These you dont you set the the first time and thats it. You put them in place and lock down the leaver and you done. I feel so much better now with these. Chock & Lock Deluxe 2 pk. Made by Ultra Fab Products. I also want you to know i have nothing to do with this company I just want you all to see this product I think it is worth the money and safety.