box cutters are safety knives patented safety features which are specially designed to prevent any accident.The user can manually adjust how far the blade extends from the handle and the knife can be used to cut the tape sealing a package without damaging the contents of the package. For example the automatic blade box cutter "shoot-back" into the handle in response to any uncontrolled movement - even with thumb on the slider, few model have the sleeve slides up and down on the handle that let you cut while maintaining blade contact with the material, holding the blade in place during use and covering the blade when not in use.