Pocket Knife Sharpner With Key Chain to fit on Key Ring for Swiss Army Knife, Bowie Knife, Buck Knives, Pocket Knives, Hunting & Tactical Knives. Just 70mm x 25mm in size and only 6mm thick, this sharpener is small enough for a key ring or keychains. The loop key chain fastener allows removal from your keyring without removing other items, ready for action in an instant. Machined from a solid ingot of light, strong military grade aluminium, the AnySharp pocket knife sharpener is supremely robust. With fixed tungsten carbide tools, there are no movable or removable parts, so there is simply nothing to break. It should last for many years even under extreme conditions. The integral finger grip ensures no slips or accidents!