Works as intended. Light weight. You should always have one in your bag, especially when traveling. Car garages tend to not have anything that fits presta.
Pretty small, so make sure you have a pocket/bag/magnet or some other way to keep track of it or you'll have a hard time finding it when you need it (or not notice it's been lost until its too late!). Just the reality of having just a small tool, but this size means it always fits in my small little tool pouch. I keep it in a tiny ziplock with my spare valvestems.
Be advised that this is a single adapter, not a pair. I was misled by the photo.