http://www.buffwear.co.uk/

Hello, thanks.
They're not technical gear, don't worry, they are stretchy headband type things (don't be put off by the odd ways that they suggest you wear them!) that can work just like hair bands do. If that makes sense. I wear one around my neck to keep my throat warm and sometimes over my mouth and one to keep my ears warm. they don't have to come in silly patterns either! I also wear mine under my climbing helmet and when my hair's looking pants when camping and.. the list is endless...
Not really a necessity but I don't know what I'd do without mine

cold air is drier so as you breathe you lose moisture. I'm told that asthma can be related to dehydration so if you cover your mouth/nose when breathing it catches some of the moisture and you can breath it in again. Or so runnersworld in Canada told me!