3M Peltor XSeries CapMount Earmuffs, NRR 25 dB, One Size Fits Most, Black/Chartreuse X4P3E (Pack of 1) A universal mounting attachment fits most hard hats. Stainless steel band construction resists bending and warping to offer consistent pressure over prolonged wearing periods. Earcup pivot points tilt for optimum comfort and efficiency. Replaceable ear cushions and foam liners (hygiene kit HYX2). Noise Reduction Rating (NRR)a 25 dB. CSA Class A