They're great for my purposes: I use them to get to valves on kids' bikes that come with a "hard" bike pump (the one that has a huge head and locking lever). See photos of what I'm talking about. I am very happy that I have something that works with every bike pump and every children's bike. Even our stroller has a hard-to-reach valve that I will use it for. The only real problem is that the twisting cap that attaches to the valve seems to be too long: you have to twist for a while before it locks into place. Otherwise I would give them 5 stars.
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