These are excellent guides for your trailer. They are fairly easy to install and the only reason I gave it a four star is because the brackets had to be cut. They are heavy material and it could be difficult to cut if you don't have the right tools to do so. With that said they use two u-bolt brackets apiece to attach to the trailer frame in a cross pattern fashion. They bolt down really tight and the guides are basically PVC pipe. That is nice so if they break you can easily replace them at your local hardware store. They're also capped off by flashing solar LED lights. You may want to check with local authorities if you can drive with those at night as they do flash red. I bought them so that I could back the trailer up without the boat on it. It's very easy to lose track of the trailer without any type of guidance. This should help tremendously while retrieving the boat.
M. Bucy 
