Helmet's emblem or logo is characterized by a minimalistic face made up of a simple circle for a head, two dots for eyes and a straight line for a mouth.
and other things of that nature.although it can be used in a good way like so...
Mike: dude i got the best Helmet last night.
Tyler: she spitshined your Helmet?
Mike: yeah i whipped out my Hoag and she went to town grinding my Helmet
Mike: (yelling at in a movie theatre) hey ho! whatch out, i drank to much soda now i gotta piss!
Gabe: shut the fuck up Helmet-shiner!