Our neoprene irrigation dam material is made in America out of a woven nylon mesh coated with synthetic rubber.  Neoprene material will not rot or mildew, and it is difficult to shovel cut.  It also retains its flexibility in the coldest irrigation water.  All pre-cut and rolled dams include a six-inch loop sewn using a double-needle lock stitch with 5 to 6 stitches per inch.