An impact absorbing, modular helmet that uses impact absorbing layers outside the hard casing of the helmet to prevent and/or reduce injury to the user is described. The protective layers on the outer side of the hard casing increase the time of impact and thereby reduces the intensity of the impact forces to reduce their injury potential. The outermost layer would preferably be made of lightweight yet rigid, durable material made of polymers, composites or metal alloys with a low friction coefficient. Subsequent layers may be made up of a polymer honeycombed structure and a uniformly consistent impact absorbing polymer material. These impact-absorbing layers may also be made and used as an independent, detachable, external protective cover that may be attached universally over hard casing helmets.