Dave5N said:ASDA £5. Get in.
I bought one of those, and wore it for all of 10 minutes before shoving it straight in the bin. Damn thing nearly choked me to death. But then, that's what happens when a clueless beginner like me buys a cheap helmet from a supermarket.
I now understand that a helmet should fit snugly enough that it does not wobble from side-to-side. And that tightening the chin-strap until you are blue in the face is not a solution if it does
I highly recommend the type of helmet that has a rachet-type mechanism at the back. This tightens the helmet itself to fit your noggin perfectly. Then, the chin strap can be worn comfortably.