The Biker knuckle OTF is one of the toughest knives we carry. It is a double action OTF knife with 440 stainless steel blade. The knuckle handle is full aluminum zinc alloy that includes a pocket clip and glass breaker stub. The glass breaker is a great tool to have for emergency situation where a window may need to be broken. The side of the handle features a slide that you push up to deploy the blade and in the same motion pull back to retract. This blade action is called dual action and is a very popular feature on knives today. The spear point blade is made from two tone black and satin finish stainless steel. The tactical sheath is made from nylon with a plastic clip an easy detachable Velcro belt loop.