EXCELLENT GLASS FILES! X-FILES! SO GOOD IT'S SPOOKY! If you've ever used a really good glass file, I don't need to convince you. If you haven't, they're life-changing. Better than emery boards, better than buffer boards, better than metal files, better imo than Diamancels. Of course, you've probably seen or used some (like the tiny purse files that sometimes show up as freebies in Nerd orders) that have a sprayed-on grit finish. NOT THESE GUYS. True Czech etched glass, with a smooth yet powerful filing surface on both sides -- they give a super-smooth edge, and are much more gentle on thin weak nails that're prone to peeling and splitting. Also effective on fake-ified nails! So if you've got acrylics, gel nails (or epoxy patches and a random whole glued-on fake nail or two like I usually do because clumsy) they'll work wonderfully on those too.
These are about the same form/size as OPI Crystal Files -- just shy of 5.5" long, a mere 2mm thick so they're easy to maneuver around edges and corners, and with a pointed tip that's handy for cleaning under free edges. Yes they're really glass, so they'll likely break if you drop them on a hard surface. But barring that, they're quite sturdy and the file surface is washable/sanitizable and the grit lasts aaaaages. These guys are permanent residents on my coffee table, bedside table, and desk.
Colors vary, so rather than trying to track inventory on a dozen different styles (esp since they come in bulk sets and I can't order individual colors), how about I pick one out just for you? But feel free to note in the Preferences box if you have a strong aversion to a particular color -- e.g. "I loathe red" or "I effing hate turquoise" -- and I should probably be able to select one you'll love!