The OLFA Rotary Cutters are premium quality that ensures reliability and precision! The small 28mm enables curved and intricate cutting, ideal for miniature quilts. Replacement blade RB28. The 45mm is the most popular rotary cutter for quilting, sewing and craft projects. Replacement: RB45. The largest rotary cutter with a 60mm blade is ideal for cutting multiple layers of fabric. Replacement blade RB60.