Check the listing for details. Picatinny rail vise block - Gunsmith tool. Color: Gray, Condition: New. Listed at 12.95 USD. You are purchasing a gunsmith/armorer's vise block tool. No firearms or firearm parts are included. The picatinny rail vise block is an innovative and simple tool designed for regular maintenance such as cleaning, inspection, and "low load/low impact" type armorers/gunsmithing work on your firearms(do not use for barrel nut tightening). It’s a ready to use, simple snap on and off design for any picatinny rail interface, utilizing a standard bench vise. The picatinny rail vise block provides a safe and secure hold within the bench vise jaws. For example by mounting the vise block onto your picatinny rail, you can position your bolt action upper receiver in a more desirable position for cleaning from the breech, or inspecting the chamber and barrel.The vise block is constructed of durable nylon that is resistant to chemicals, cleaners,and solvents with a non-marring contact surface.The vise block works with any caliber firearm or part that has a picatinny rail interface.