The PetSafe Deluxe Bark Control Collar features 18 levels of correction and is one of the smallest unit available at only 1.7 oz. The patented Perfect Bark Technology ensures that only a combination of both sound and vibration from your dog can activate the collar. A harmless static corrrection is then emitted to correct the behavior. Adjustable collar for neck sizes 6"-28". Also comes with a training video. Shipping weight: 1 lb