This straight edge trimmer has a measuring surface of 5″X12″ with an extended measuring guide to 12″X15″ that is marked with .25″ grid lines. There are also rulers on both sides of the blade. The extended ruler folds at a right angle for a precise 6″X6″ cutting guide. A magnetic cutting arm tightly holds paper. Use replacement blade 54-00057. A replacement for Martha Stewart Simple Paper Trimmer 12
