Ultimate hearing protector designed to be Peltor Sport's highest noise reducing earmuff. Superior comfort and protection. Adjustable, vented headband design reduces heat build and improves comfort when worn with hats. NRR 30 dB Peltor Sport Ultimate hearing protector is Peltor Sport's hightest noise reducing earmuff providing a noise reduction rating (NRR) of 30 dB. This earmuff design is lightweight and provides superior comfort and protection for extended wear. Adjustable, vented headband design reduces heat build and improvES Comfort when worn with caps and hats.