Abstract: An apparatus includes a body member which has a pair of guide surfaces. A blade projects from a first of the guide surfaces and the cutting edge of the blade forms an acute angle with the first guide surface. The plane of the blade forms an acute angle with the second guide surface thereby facilitating a clean cutting action. The angle of the plane of the blade effectively maintains contact between the guide surfaces and the carton being opened and minimizes any tendency for the carton opener to leave the cut. The body member includes a curved portion forward of the blade and a projecting wall portion which serve to position the hand of the user in the correct ergonomic position for safe and efficient operation.

Abstract: A cutting implement employing a pair of rollers placed vertically one above the other, the rollers having sharpened edges that slightly overlap and touch each other at a selected position, forming a cutting point where they touch. When the rollers are rotated, the sharpened edges form a continuous cutting edge for cutting material such as most paper and plastics. The rollers are provided with a degree of toe-in in the direction of rotation to insure that they remain in contact with each other during the cutting process. The rollers are rotatably mounted to a stiff carrier to provide dimensionally predictable location of the rollers with respect to each other, and to insure the smooth flow of material through the rollers as the material is being cut.