This 45mm Rotary Blade Refill set is designed for use with OLFA 45MM Rotary Cutters. Each one features a sturdy and durable tungsten carbide tool steel construction to ensure high performance and a long lifespan. These round blades are easy to install and replace and they re compatible with model numbers RTY2 RTY2/DX RTY2/SCB and PIK-2. They come in a handy blade holder to keep them centrally located and secure for safety purposes. Each pack includes five of these blades and they come in a carrying case that s made of plastic.