Fits up to 26 inch necks. For dogs of all sizes. Water resistant. Flea & tick for dogs and puppies. 14 month protection 2 collars in one package, each providing 7 months protection. Kills & Repels: fleas; ticks; flea eggs; flea larvae. Prevents: Flea eggs from hatching. Collar with reflective technology. Full body protection. For more information, call our experts at 1-800-275-1414 weekdays. 9am-5pm E.S.T.