This is a well-designed sharpener. Not only compact and easy to carry, it is quick to set and simple to use. It won't make sharpening a chain saw any less tedious, but will ensure it is performed accurately.
It is about as straightforward to use as a pencil sharpener; just set the jig to the bar, position the pawl against a tooth, insert the burr through the guide bushing, and crank the handle.
To sharpen the next tooth, retract the burr, pull the chain forward, and repeat the process; as you advance from tooth to tooth, the pawl acts as a stop to ensure accurate and repeatable tooth positioning.
Results are predictable, and chain wear is kept to a minimum. About 3" x 4" x 2-1/2" wide, the anodized aluminum jig comes with a removable crank handle and a set of guide bushings (for alternating right- and left-raked teeth) to sharpen at a standard 30° rake angle; a set of optional bushings for 25° and 35° are available separately.
A soft-shell case (with nylon straps for carrying it on your shoulder or belt, and pockets for extra burrs and angle guides) is included. The US-made carbide burrs for 5/32", 3/16", 13/64" and 7/32" teeth are sold separately – please check your saw manual for tooth size before ordering.