Popular size for your medium and heavy-duty projects 45mm Original Rotary Cutter has changed the quilting and sewing industry. The most popular size available, this cutter features a durable handle with a blade cover for safety. The cutter is a rolling razor blade used to cut materials into shapes, strips and pieces for sewing, quilting and craft projects. The blade is made of high quality tungsten carbide tool steel for unparalleled sharpness and superior edge retention. Designed for both right- and left-handed use. Satisfaction Guaranteed.