This Diafold Single Sided Sharpener is a great, low-cost sharpener for knife and tool edges. Measures 9.375" when opened and only 5" when closed. It has an extra coarse 220 mesh/60 micron sharpener (as indicated by the black hinge) that is best suited for axes and re-beveling knives. It folds up to save space and to protect the sharpener from damage.