Troy Rail Covers easily slide onto a MIL-STD Picatinny Rail and locks into place with a built-in retaining clip and can be adjusted with a bullet tip; no tools required. Constructed from durable, heat and chemical-resistant synthetic polymer resin" each rail cover is scientifically engineered and proven to reduce heat transfer and hand abrasions. Features: Black finish 3 pack Picatinny rail 6.2 inches length