It's a very good glass nail file. Has a fine grit that won't damage your nails. The price is a bit high but it lasts a long time - i've had mine for about 2 years, frequent use (i avoid cutting my nails, only file them down), and it hasn't lost any of the grit.

The file itself is 1/2in wide, 5.5in long (4in with grit and 1.5in smooth - handle). The sides are smooth so you can only file top or bottom, not from the side.

It has a sturdy plastic cylindrical case to store, which is great because glass files don't bend so a flimsy shell does nothing to protect it. Inside of the case has a plastic mold to hold the file in place. The case is about 10% larger than your average pen, and fits in a purse nicely.

Cleans easily with soap and water (or just water).