Looking for hat stretcher recommendations

Does anyone have any recommendations on hat stretchers? Looks like lots of different options on Amazon. Any little things I might want to look for that sets one apart from another?

I recently got a fitted New Era NBA cap in the 7 3/8 size. It’s just slightly too tight. But the 7 1/2 is just slightly too big. So I was thinking maybe a hat stretcher to get the 7 3/8 to fit a little looser without being too big. Seems silly sizes so close have such a different fit but sometimes I’ll find 7 1/2 hats that fit nicely.

Thanks in advance for any suggestions.