The hard core, the outlaw elite, were the Hell's Angels... wearing the winged death's-head on the back of their sleeveless jackets and packing their "mamas" behind them on big "chopped hogs." They rode with a fine unwashed arrogance, secure in their reputation as the rottenest motorcycle gang in the whole history of Christendom.
Hell's Angels: The Strange and Terrible Saga of the Outlaw Motorcycle Gangs (1966)