This slide is of decent quality, but I did expect something a little more polished from Fender. It's unbranded and nothing, that I can see, sets apart from other inexpensive glass slides I've seen elsewhere.
I ordered a large slide based on other reviews because I have relatively large fingers. Unfortunately I find it too big! The fit is not as snug as I would have liked. I'll be getting a medium one instead with my next order. For reference, my middle finger is 7cm in diameter at the second joint.
Sound wise it's lovely. It produces a lovely airy, liquid tone, which I personally prefer over the sound of a metal slide.
If you're worried about the size, perhaps buy one of each to test them and return, sell or give away the one you don't need. The reviews here offer different opinions on sizing and this appear to be the kind of product you really need to test before settling on!
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