Not for large/round heads
347243
These glasses seem pretty sturdy and they're very cute, however I have a fairly large head and they were way too narrow for me. I wish they'd sell them in different sizes.
1975888
Seems like a nice hat for the price.  However, be wary if you have a large head. It does not fit comfortably.
3850078
These fun glasses are not really small - the lenses are 2" in diameter and are too big for me to wear comfortably.  I have a small face, so they would probably fit a man much better.  They also arrived bent, and I couldn't get them to sit straight on my nose.  I could have returned them for a replacement, but I wouldn't wear them much because they are really too big for me.  Unless you have a fairly large face or are just using them with a costume, I wouldn't recommend them.
1612291
I don't have a large head, but these were too small for me.  I tried them once to see if maybe I would get used to them, but in addition to being uncomfortable, they weren't great at blocking out the sun.  I'll be returning them.
3480414
The size of these as described in the information section sounds reasonable. I understood that there would be some leeway, and that they would fit most, if not all, heads. Unfortunately, they do not. These are tight - very tight - so tight I had trouble getting them off. How big is my head, then? Not big at all. While I'm not a pinhead, I do have a narrow, oval female head, not wide at all. I would feel fine buying these for a toddler. They fit like swimming goggles on adults.
1708936
If you have a rather large head like me, these won't be very comfortable to wear. I used these for a few hours straight and found myself getting a headache around my jaw bone due to the pressure being put on my ears. And fully expanded, they did not quite reach down far enough to cover my ears. I ended up putting them on at an odd angle to get them to fit over my ears.

The fit is disappointing because I really like the sound quality and the Bluetooth connectivity to multiple devices worked extremely well.

If you have a Bose retail outlet nearby, I suggest going there first to try these on before buying them.
4414214
It was quite large for my head and I needed to return it. Definitely not a "one size fits all"
3325917
bought these because they are adjustable and I've got a small head....with it as tight as I could get it,it was still way 2 baggy,too deep as well.it pushed my ears down....don't buy unless u have a gigantic head
2269150
I do have a slightly larger head, but these were not comfortable to wear.  They did seem to block the noise, but I couldn't wear them very long.
3251968
Nice looking hat -  but back/cap part way too large for most normal heads. Tried on a few people. I have to fold it under to make it fit..
4829489
This is a well-built product made by a good, reliable company, it cuts-down on noise as advertised, and they have a nice and tight fit. No problem so far. The only problem is that this item will only fit your noggin if you're a pinhead.....no offense, m8. When I put these on my head, the bottom edge of both earmuffs only covered about 90% of my ears, they don't cover my ears completely. Bummer. They should have made the head-piece adjustable to fit all sizes of heads. 3M, if you're listening, use your head when you design a product, for crying out-loud. I digress. So if you're a pinhead, buddy, this item will fit you, and you'll have something to proud of in life  (c:
8454
Returned. Very too large for my liking and too tight. I have a pretty small head too, so I did not expect them to be that tight.
2794037
Good quality,  very pretty.  Very, very snug,  gave me almost an instant headache.  I believe my head is average size--it could be larger than the average,  I do have long hair but it is fine.  I have a large build so maybe if you are more petite with a smaller bone structure,  maybe it would be a better fit for you.
3784291
These hats are intended for people with little bitty teeny tiny heads. If your head is larger than a tennis ball you'll want to look elsewhere.
3903282
The one I got was way too loose even for a large head. I had to tighten it as tight as it would go and still needed to tie a knot in it to prevent my glasses from falling off when bending over working on things. I read the review from someone with a small head and figured I wouldn't have that problem, but I did. Wherever it was made they must have heads the size of large watermelons. I'll keep them only because it's a bigger hassle to return them than it's worth and I was able to jerry-rig it, However, leaving an ugly knot at the back of my head.
1432354
I thought I read in the description that this hat would fit a woman's head but it doesn't.  It pops up and does not lay against the head at all.  Now I'm stuck with it bc I don't want to pay return postage.  The material is silk-like, which is why it doesn't fit correctly.  My head measures 22 inches round - so buyer - beware!
4826264
Apparently made for people with much smaller heads than mine. Not stretchy at all, so even if it fit, it wouldn't stay in place. Perhaps under a helmet, but not for workout gear.