General-use thermoformed liners are made from >60% recycled ABS, approx. 3/16" thick. UV inhibitors are added to the material, but for applications where they will be exposed to direct sun, field painting is recommended. All liners are created to a +/- .125" tolerance. Liner thickness will vary slightly from the ends to the center, and walls may flex outwards on longer liners. Drains can be installed by installer in any location your application requires.