This can be used for inhalation for dogs and cats with asthma and bronchitis. I purchased it on Amazon about a month ago for 5999 yen, but I'm selling it because I stopped using it after a few uses. There are no noticeable stains and it's in relatively clean condition, but please understand that it is a used item, and if you are concerned, please refrain from purchasing. The silicone mask that goes in the mouth has been cleaned and disinfected. The size is approximately 6.5cm in diameter and approximately 4cm in inner diameter. It was the perfect size for my 3kg Yorkshire Terrier. *Please make sure to check the shape of the inhaler that can be attached before purchasing. As shown in the 5th photo, it is oval. Please note that it cannot be attached to a round inhaler. Please also refer to the 8th and 9th photos. Please note that we cannot accept returns for reasons such as the size not fitting. There are no instructions, so please feel free to ask any questions you may have (^ω^) Thank you! xieddd Aerochamber for dogs and cats, asthma, wheezing, coughing, inhaler, metered dose inhaler, pet bronchitis, canine tracheal collapse, bronchitis, feline asthma