Review on EZ Shim Heavy Duty Shims - Plastic - 7.9 Inch by Kelly Noonan

Very strong and hard enough not to dent or flatten. It looks like it can handle areas of high humidity and extreme outdoor weather. It's very thin on one side, so you can handle even the slightest wobble. The thickest side is probably only about 1/4", so it probably won't work on a severely uneven surface unless you want to glue multiple epoxies together.