OLFA rotary knife wheel cutter is designed for cutting tight corners, curves, and circles on cloth, paper, vinyl, film, thin leather. Designed for use in intricate and detailed cutting, this small rotary cutter is one-of-a-kind. Perfect for curved piece quilting, trimming seams, template cutting, scrapbooking, and miniature quilting. Perfect for use on our self-healing cutting mats. 18mm diameter rotary blade. OLFA RTY-4 rotary cutter knife uses RB18 replacement blades (shown at right).