For puppies and dogs up to 28 inch neck. Sustained release pheromones proven to modify behavior. Recommended for problems such as: separation anxiety; destructive behavior; inappropriate marking. Lasts up to 30 days. Effective stress reduction for use both at home and on the go! SettleDown Pheromone Collar helps dogs in fearful or stressful situations (separation anxiety, fireworks, thunderstorms, visitors, new puppies, new baby, vet visits, traveling). SettleDown Pheromone Collar provides a convenient alternative to diffusers which are limited for use in the confines of a designated room. SettleDown Pheromone Collar goes where your dog goes whether it is at home or on the go! How does it work? SettleDown Pheromone Collar mimics the pheromone that the mother dog produces to calm and reassure her puppies, and the lavender and chamomile provide a soothing fragrance. Dogs recognize these pheromones throughout life. It mimics the natural way to help dogs cope with new and fearful situations. Sergeant's is committed to providing high quality products. For animal use only. Visit us at: www.sergeants.com. Made in USA.