20' Side Walls. Fits our 20'X20'10x20 12x20 heavy Canopy and jg Canopy. Each side wall is sold one piece per package and includes grommets around the edges for attaching to the frame. The side wall is fabricated using 6 Oz, 12 mil polyethylene and 16 MIL is 100% water proof and UV resistant cut side 4"to 6" short