Today's knives are made from the hardest of steels and you simply cannot sharpen them with an Arkansas Stone because the steel is harder than the stone.  This little pocket wonder has rods embedded with diamonds to sharpen the hardest of steels.

Coarse diamond rods for aggressive sharpening
Fine diamond rods for razor sharpness

Do not confuse this diamond sharpener with those inexpensive crock stick pocket sharpeners that sell for a buck two ninety eight at Wally World.  This will sharpen knives, not merely hone them.

This is a compact diamond sharpener, small enough to fit into your kit, yet effective enough to sharpen your survival knife.

Made by Gerber

A dull knife is a dangerous thing.