The secret is diamond-coated spring sharpeners built into the folder frames, placed at the precise angle to give the blades a sharpening stroke as they are closed and opened. Not only do you never need to sharpen the Edgie blade with stones or wheels, but you should not, because it may alter the blade's proper self-sharpening edge angle. Of course, it is important during a long cutting work session to periodically open and close the blade to maintain the edge.
The Original CRKT Edgie is a single-edged utility knife. The 2.875" high-carbon stainless steel blade in satin finish features a strong full-width spine. For strength and long life, we've used our InterFrame build, with two stainless steel liners and stainless steel back spring, all in satin finish. The injection-molded glass filled nylon scales have castellations at the spine and a checkered inset pattern to enhance grip.
A note about the cutting edge. The diamond sharpening strips cause a tiny burr to form, acting as a microserration, which helps cutting action. This makes the Edgie tops for cutting cardboard boxes, rope, cord, garden stalks, and even ripe tomatoes. The more you sharpen Edgie models, the more pronounced this microserration honing becomes. For those who are used to a traditional Razor-Sharp edge, it may be disconcerting, but it is the secret to why the blades cut through fibrous materials so effectively.