Insecticide-free Catchmaster Spider Web Fly Glue Trap is for use in and around barns, milking parlors, milk rooms and other areas of high fly density. Spiderweb Fly Glue Trap combines pheromone and food attractants with a superior glue formula capable of catching over 100,000 flies per roll. 12"W x 23'L with double-sided adhesive, designed to be hung horizontally. Can be pulled out to various lengths which, when filled with flies, can be rolled up exposing new glue surface.