Box cutter blades are compatible with Slice box cutters, pen knives and the Slice Mini Cutter. These 100 percent zirconium oxide blades retain their edge 11 times longer than steel and feature proprietary finger-friendly grind. Ceramic blades require no oil coating or special maintenance. They're nonsparking, nonmagnetic and never rust. Rounded tip offers extra protection against accidental puncture injuries. When you need a fresh edge, simply reverse the double-sided blade.