[uncleboo]

I've done a few in the past using cellular PVC. It's the stuff they are selling at Lowes for trim boards. It's very durable and will last forever. I used this because it is a bit softer so I could use stainless steel staples to hold the fabric to the backer. Using this material allows you to use stainless carriage bolts available at a well stocked marine supply. You can countersink the nut on the back side so the bolt won't spin and allows the pad to be installed flat. So far, the ones I have made are holding up. I made them for other people so I don't have pictures.