The Rex Specs Ear Pro K9 hearing protection, by Zeteo Tech, was developed and designed specifically to protect military working dogs from temporary and/or permanent hearing loss that can arise from sudden, high impact, noise exposure. Whether on a mission, at the range, on a motorcycle, or at an rock'n'roll concert — Rex Specs Ear Pro will protect your K9's ears and will limit your dog's hearing damage over time. PRODUCT FEATURES: Sound absorbing foam padding for ultimate protection 4-way stretch fabric is lightweight and breathable - for extended duration use Easily integrates with other gear like goggles and muzzles Low profile design for stable protection even in tight places Flexible design seals around ear for maximum sound protection Hood like design uniformly distributes pressure to be held in place without straps WHY REX SPECS EAR PRO? Superior materials. The Ear Pro have been constructed with the best low frequency noise blocking foam Rex Specs could find and test. Hearing protection is only as good as the fit. There are no holes or penetrations in the foam. No need for adjustments, or straps that need to be fine-tuned for a good fit. If the Ear Pro moves a bit - it still works. Other products lose effectiveness as the product moves off the ear. AVAILABLE SIZES (HEAD MEASUREMENT - FROM UNDER THE CHIN TO OVER THE CROWN OF HEAD): No2 Medium 13" - 15" | 33 - 38cm No3 Large 15" - 17.5" | 38 - 44cm No 4 XLarge 17.5" - 21" | 44 - 53cm PERFORMANCE OF REX SPECS EAR PRO We have adopted the best practices used by the National Institute for Occupational Safety and Health (NIOSH) to conduct real ear testing on dogs to determine the effectiveness of Rex Specs Ear Pro. These tests were run at lower frequencies as they are the hardest to attenuate. Real ear testing was conducted in a sound booth with the noise exposure set to 95 dB A (white noise). 95dB A examples: tractor, blender, motorcycle, power tools, Bell UH-1 helicopter See graph below for results. At very low frequencies (20Hz - 120Hz) Rex Specs Ear Pro attenuates, or reduces the noise exposure between 18 dB A and 24 dB A. As the frequency increases, so does the effectiveness of the product. Testing by Dr. Peter M. Skip Scheifele PhD, LCDR USN (Ret.) A few reasons Rex Specs Ear Pro performs better than the competition. Superior materials. We’ve constructed Rex Specs Ear Pro with the best low frequency noise blocking foam we could find and test. Hearing protection is only as good as the fit. There are no holes or penetrations in the foam. No need for adjustments, or straps that need to be fine-tuned for a good fit. If the Ear Pro moves a bit - it still works. Other products lose effectiveness as the product moves off the ear.