This durable and waterproof microcollar has Light Touch technology that provides 10 levels of self-adjusting correction. The patented Perfect Bark™ detection ensures your dog's bark is the only one that can activate the collar. The QuickFit™ buckle provides a perfect fit for neck sizes up to 34". A two-color LED indicates when your battery is low and needs to be replaced. Uses PetSafe RFA-188 battery module (included).