In the installation guide for the Andersen, it shows how to install the left and right brackets on the trailer frame (this is where the chains attach). To secure those brackets from their initial perfectly ok slippage when they are first used, Andersen designed a set screw for each of the 4 backets. Optionally, you may just do a small spot weld on the side of the bracket. Others have said they liked doing the spot weld as it appears more secure than the set screws. Andersen says either is fine. I chose the spot weld option.
