The Dahle 507 Personal Rotary Trimmer with a 12" cut length is lightweight and portable for just about any application. It features a ground self-sharpening blade that cuts in both directions a triangular aluminum guide bar for strength and an automatic clamp to prevent your work from shifting. This German engineered cutter is ideal for trimming paper photographs and cardstock. SELF-SHARPENING- No need to worry about replacing dull or worn blades the self-sharpening system sharpens as you cut to maintain a perfectly honed blade. The precision graduated edge will remove even the tiniest sliver of paper and produce a clean burr-free cut. TRIANGULAR GUIDE BAR- The aluminum guide bar provides strength and durability. The triangular design provides a smooth stable track for the cutting head. AUTOMATIC CLAMP- The trimmer's integrated automatic clamping system provides hands-free even pressure as you cut to prevent your work from shifting. METAL BASE WITH GUIDES- For measuring the base features carefully screened rulers and guides to help align your cuts. For added convenience the grid includes standard-sized guides for trimming photos and documents. Dahle's 507 combines all the precision you need with a lightweight portable design. It's a popular choice among photographers craft enthusiasts and office professionals.