CITADEL TOOLS KNIFEFixed single slot blade barrel, ensuring perfect alignment Ribbed shroud behind the blade, allowing safer downward pressure and maximum precision Ergonomic handle to reduce hand fatigue, and prevent rolling on your desk Back weighted design, so its less likely to fall with the blade down Blade changing thread recessed into the handle so the blade doesnt loosen during use Blade cap The Citadel Tools Knife also comes with a pack of six replacement