COSYWORLD Flea and Tick Collar - Adjustable & Waterproof Flea and Tick Control Collar (DOG S) ADJUSTSBLE SIZE: The length of the collar is 25" ( 63.5 cm ), it can fits for any types of doggy from 8 weeks old. MORE LASTING: under normal circumstances, this product lasts for eight months (even in water) MORE SAFETY: New 100% natural formula doesn't contain any toxic chemicals. More effective flea and tick prevention for dogs than other collars and still safe and hypoallergenic for you and your pet. AMAZING GIFT: Flea and Tick Collar will be a great gift for pet lover. Especially, when the flea season comes, this is a must have item for the dog. You can choose our flea can tick prevention as a gift for your own dog or the dog of your friend or your relatives. SATISFACTORY GUARANTEE: We take great pride in the quality and efficiency of our dog & cat collar and we know you and your pet will just LOVE it! If you're not absolutely thrilled with the results, we'll offer you a prompt.Please contact us at any time.