The OLFA RB45H-1 Endurance replacement blade is built for longer-lasting rotary cutting in quilting, sewing, and crafts when you want fewer blade changes. This tungsten steel blade is hardened for extended life and is compatible with all OLFA 45 mm cutter handles, supplied in a protective storage case. Keep it stored in its case, install with the cutter secured, and swap blades carefully to maintain smooth, accurate cuts.