Breathable “floating” woven polyester material. Lies over beds to extend growing season. Acts as a mini greenhouse allowing air and water in. Resists frost. Won't overheat or crush your seedlings. Protects against root maggots, flea beetles, leaf miners, carrot rust flies, birds and other pests. Also use to protect tender crops at the end of the season. Lasts three seasons if kept our of summer and winter weather. Won't snag your hands.