VEVOR Pond Liner 13 ft. x 20 ft. 20 Mil Thickness High Tensile Tear-Proof Flexible HDPE Pond Skins for Artificial Lake, Black FS-1320T0.5MMHBQ6V0 - The Home Depot
New Vinyl Pond Liner: 20 oz., 22 mil, Black/Black - Click for Sizes - billboardtarps.com
Classic RPE Pond Liner
VEVOR Pond Skins 20 ft. x 25 ft. Pond Liner 45 Mil Thickness Pliable EPDM Material for Fish/Koi Ponds Water Gardens, Black CTFSMHSEPDM20SZTDV0 - The Home Depot