3M™ Optime 98 H9A Earmuffs, 25 dB NRR, Yellow/Black (MMMH9A) Each3M Optime 98 H9A Earmuffs 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. Global Product Type: Over the Head Ear Muffs Material(s): ABS Plastic Ear Cushion Material: Liquid Foam Noise Reduction Rate (NRR): 25 dB Ear Muff Style: Over The Head Weight: 0. 55 lb Color(s): Yellow Black Product Biodegradability