Mutt Muffs are specifically engineered to meet the contour of a dog's head to provide the best passive sound reduction possible. A dog's hearing is much more sensitive than ours. It makes sense that if you are wearing hearing protection, so should they. These are designed not to block out all sound, but to be a passive, noise reducing device that will make a ride in an airplane or time spent in any noisy environments to create a comfortable experience for your dog. We proudly sell these to our by RAAF Base Dog Squads, Police Dog Squads and SAR dogs. They can also be used for Gun Dog Work, Hunting Dogs and for dogs who are sensitive to sound. Features: Comfortable and lightweight foam padded ear muffs that cover the dogs ear and seal completely for both comfort and sound reduction Adjustable straps Specifically designed to meet the contour of your dog’s head, perfect for helicopter airplane noise and gun work noise, but reduces harmful noise in nearly any environment. Colour: Black. Please note the chin strap clip is stainless steel, if using for scanning, MRI's or medical use and require all plastic hardware please let us know at [email protected] and we can arrange this for you as a special order. Mutt Muffs materials were selected on the basis of their usage in human hearing protection devices that gave an average advertised reduction of 20 dB. So that, or better, is the db reduction number Mutt Muffs were designed for. The second consideration was the high frequency noise that is beyond the range of human hearing. Assuming the noise reduction properties of Mutt Muffs is in the 15-25 dbs. range at human frequencies, we can assume an even better number in the high frequency range for the simple reason that higher frequency, shorter wavelength sounds are easier to diminish then the longer wavelength sounds that fall within the human hearing range. If we are out of stock, we can order for you as a special order item - contact us at [email protected] and we will happily assist you with an order. What Size? The overall circumference measurement of your dog's noggin at the largest point is the best determination of size, because if you choose a size too large, the muffs won't seal well against his head, and you lose all the sound-reducing properties you were shooting for. The circumference is the measurement that would create a circle by going across the top of the dog's head, over the ears, and under the chin. Our dog's weight is also a good indicator of which size to choose. Size Guide: The overall circumference measurement of your dog's head at the largest point is the best determination of size, because if you choose a size too large, the muffs won't seal well against their head, and you lose all the sound-reducing properties you were aiming for. The circumference is the measurement that would create a circle by going across the top of the dog's head, over the ears, and under the chin. Your dog's weight is also a good indicator of which size to choose. Please see images as well for size guide details Actual Size of the ear muff dimensions below: Size Max Width Max Height XS 1.5"3.81 cm 1.625"4.12 cm Small 1.75"4.44 cm 1.75"4.44 cm Medium 2.5"6.35 cm 2.5"6.35 cm Large 3.25"8.25 cm 3.25"8.25 cm XL 4"10.16 cm 4"10.16 cm Note: Dogs should always be supervised while wearing Mutt Muffs. Care should be taken when your dog is wearing Mutt Muffs at all times.