This simple little gadget is handy to carry, and easy to use for touching up your blades on any knife when something more sophisticated is not available.  One side reshapes the blade bevels, and the other side finishes the edges to razor sharpness.  The only thing left to do is a few passes on a leather strop, and your knife is back in business.
 
SPECIFICATIONS
 
Pocket-sized compact one-piece plastic construction
Carbide blades in "V" formation re-bevel your knife's edge
Ceramic rods polish and finish the edge
Rubberized base for stable holding on flat surface
Key chain
 
Comes in red or black