BEAUTIFUL IN-GROUND VINYL LINERS OUR DESIGNER PATTERNS WILL MAKE YOUR POOL LOOK LIKE NEW! Made from 100% virgin vinyl, our super strong liners are built to last. Each liner comes with a clear protective coating that protects your liner from sun, chemicals, bacteria, fungus, and algae. Our liners come in 20- and 28-mil and they are backed with a 25-Year Warranty . Note: This liner is only designed to work with our NB2207 Emerald Rectangle 20' x 40' pool.