Product review (4 stars): Better than my rubber band and pliers...
The old knobs on my gas stove broke over time (the last aided by a clueless house guest) and I had a complicated method of turning them which involved a rubber band around the posts and a pair of pliers.  These fit, they look decent, and they work.  They aren't particularly sturdy and the labeling isn't great, but I can adjust the heat by looking at the flames and sorting out for myself if things need turning up or down.  All in all, way better than the pliers and rubber band McGuyvering method.