Allen Shotwave EarBud Hearing Protection | Ian Hodge
Hearing protectors | Walker's Razor Slim | NRR 23 dB
Decibullz - Custom Molded Earplugs, 31dB Highest NRR, Comfortable Hearing Protection for Shooting, Travel, Swimming, Work and Concerts (Orange PLG1) : Amazon.co.uk: Health & Personal Care
The Quantification and Reporting of Hearing Protection Attenuation -