No Chemicals-Ultrasonic Flea-Tick-Lice-Mosquito Repeller Collar for dogs cats No chemicals-effective & safe continuous delivery-ultrasonic protection dog-cat-pets collar repels fleas-ticks-lice-mosquitoes before they land fits dogs and cats with 3"-20" neck sizes. slightly audible to pets & humans replaceable 1.5v batteries included. Batteries last about 3 months. limited lifetime warranty. Send a photo of your pet modeling this collar to gainkeeper@gmail.com. It may be selected as pet-of-the-month & featured on my Amazon ad.