Heavy Duty Knife GK - A powerful and durable ground knife suitable for tough tasks such as prizing, breaking and hacking. It features a unique function for attaching the holster around a button on your work clothes so that it does not come loose whilst still being easy to remove. The blade is made from Japanese knife steel, 3 mm carbon steel that has been hardened to 58-60 HRC. The holster can be attached to both a belt and a button on your work clothes. If your belt is thick, cut away the small pin on the cover.