A protective head gear includes a protective portion for covering at least part of the back of a user's head. A headband strap is included for extending from the protective portion at the back of the user's head to the user's forehead to hold the protective portion in place at the back of the user's...http://www.google.es/patents/US7051379?utm_source=gb-gplus-sharePatente US7051379 - Protective head gear
