The PetSafe Deluxe Big Dog Bark Control Collar automatically deters annoying barking. The Deluxe Big Dog Bark Control Collar detects your dogs bark using Patented Perfect Bark technology to ensure only your dog's bark causes the correction. As he barks, he receives a safe but annoying static correction. The bark collar begins with low corrections, if excessive barking continues the correction intensity will increase. When used correctly the bark collar reduces (and in most cases eliminates) nuisance barking. Easy to use, no manual settings. Patented Perfect Bark technology for the most reliable bark detection. 10 levels of Light-Touch correction. Waterproof. Two color LED for good/low battery indication. Adjustable nylon collar for neck sizes up to 28". One Year Warranty.