Firestone W56PL452020 EPDM Rubber Pre Cut and Boxed Pond Liner, Midnight Blue, 20-Foot length x 20-Foot Width x 0.045-Inch Thick

I used it to waterproof a second story deck floor for a utility space under it. Excellent product. Heavy duty, strong, and durable. Worth the price.

So glad I made the right choice to upgrade / purchase something that is worth the price. This is a REAL POND LINER. The fact that I / we, can purchase an item such as this via Amazon is awesome. I went to many different sites, and local locations, etc. and either out of stock, had to be ordered and take weeks to arrive, or you can see they were upselling the item. This liner is working great, fit perfect and no leaks so far. durable, reliable and worth every penny. You are improving upon your home, business, community, etc. and thus make it a purchase worth lasting a long time.

This liner came in a well packaged cardboard box, folder many times, but realize the 20x20 size is super heavy. It took four people to properly move it into place. If you have a very irregularly shaped pond, like I did, you will need to spend some time trying to get the folds to look reasonable, which is harder than one might expect. Part of this is due to the thickness of the material. I recommend you only start laying this during the cooler parts of the day, as it gets super hot in the sun.

I like the quality of the liner. Just put them on my pond .

Appears to be very durable - heavy weight. Remember, you get what you pay for. Last liner was cheap, much thinner, made of vinyl, only lasted 8 year. Had become very brittle, developed holes, and leaked. This product is supposed to last 20 years. I think it will. Time will tell. So far it works well. I love it.