The Koro Pocket Gopher Trap is made of heavy duty .187 dia. mild steel. It measures 2"W x 2.5"H x 5"L. The spring is made in house of .125 music wire spring steel. This pocket gopher trap is truly a beast compared to its competition. The Koro Pocket Gopher trap is easy to use and built for years of use. The Koro Pocket Gopher trap comes with a cable anchor to secure it down.