The JAKAR mount cutter has been designed to cut mount boards with a 45-degree angle and 90 degree angle. The cutting should be done from the rear of the mount board. In order to achieve a 45-degree angle, ruler is to be placed on the outside of the aperture, for the 90-degree on the inside of the aperture. Cuts materials up to 7mm thick. Can be used for cutting cardboard, leather, paper, vinyl etc. (includes 3 spare mount cutter blades ref. 7347-B).