I purchased this 2 years ago when I first started riding, didn't understand proper fit. This helmet is an XL, I now wear a medium. I used it less than 5 times because of the fit, kept sliding down my brow. Can't return helmets, so it has been sitting on my shelf. Still have the box, bag, unopened spare parts. Not a scratch on the helmet. Bluetooth system is Uclear AMP Go 2.0, its on the helmet with double sided tape (factory supplied) so you can take it off if you don't like it.