A recent study featuring PISC Senior Scholar Kristy Arbogast, PhD, evaluated the effectiveness of two commercially marketed football products, the Guardian Cap NXT (GC NXT) and the ProTech Helmet Cap (ProTech). Both the GC NXT and the ProTech are designed to “augment the energy attenuation” of American football helmets. Each product was evaluated on seven helmet models through two linear impactor tests. Results indicated that the GC NXT reduced head impact severity by 9%, while the ProTech reduced impact by 5%. In addition, estimated risk for serious neck injury was reduced by less than 4% in both products. Effects varied among each product based on the impact condition and helmet model. Both products significantly reduce risk of head injury in American football.