Troy Rail Covers are engineered to survive the most extreme conditions. Constructed from durable, heat & chemical resistant synthetic polymer resin, the Troy Rail Cover quickly and easily slides onto a 1913 Picatinny Rail and locks into place with a built-in retaining clip. Scientifically engineered and proven to reduce heat transfer and abrasions to the operator"s hand. No tools required.- Patent Pending. Made in the U.S.A.- 4.4"- Black- Single Pack.