Sturdy earmuffs are designed with pivoting earcups for optimum fit. The H9A Model is a high protection design, for challenging work environments. Works with AO Tuffmaster® face protection system. Material(s): ABS Plastic; Ear Cushion Material: Liquid/Foam; Noise Reduction Rate (NRR): 25 dB; Ear Muff Style: Over-The-Head.