Trimmers make any paper cutting job easy and exact. The boards are heavy-duty and are the well-accepted green board with 1/2" grid. There are rulers in both centimeters and inches to help be exact in measurements. These heavy duty paper trimmers accomodate all of your crafting, office or school trimming needs. They vary in size cutting size from 11 3/4" to 36". The boards also cut cardboard, textiles, matte board, film and up to 20 sheets of paper. The non-slip feet, ergonimically designed cushioned handle, finger guard and torsion spring make the Martin Yale Paper Trimmer safe and comfortable to use. The manufacturer has a limited lifetime warranty on some parts, including the blade.