SincereetaliFeatures: Helmet Mounted: Easy to put on a helmet and fits most helmets headphones. Noise Isolation: Designed with 2 layers of professional noise-canceling foam, solid cup with high sealing, the earmuff provides good sound insulation effect, no longer be disturbed by noise. Functional: A simple way to improve sleep quality, reduce noise damage to hearing, avoid noise interference, and effectively improve work and study efficiency. Reliable Quality: ABS shell, 304 stainless steel headband, good corrosion resistance, heat resistance and oxidation resistance. Ergonomic Design: Soft ear cushion and comfortable to wear. Wide Application: For sleeping, shooting, flying, factory, construction site, etc. Specifications: Material: ABS + nylon + stainless steel + sponge NRR: 23dB SNR: 28dB Class 5 SLC (80): 29.5dB Item size: 21 * 15cm / 8.27 * 5.91in Item weight: 307 / 10.83oz Package weight: 315g / 11.11oz Package size: 20 * 14.5 * 9.5cm / 7.87 * 5.71 * 3.74in Package list: 1 * Earmuff