12 inch/30cm Desktop Rotary Trimmer. Cut up to 10 layers of paper with precision. Features include: 1/4 inch grid lines for easy and accurate measurements; blade carriage for safe and easy two step blade changes; blade carriage is also keeps the blade visible yet protects your hand; the cutting bar prolongs blade life; smudge guard to hold things in place while avoiding messy fingerprints on your paper; rail lock for safety when moving or storing your trimmer. This trimmer uses blade style F.