A well-timed tone can hush your puppy. This remarkably light, 28g collar emits an unpleasant but harmless tone to correct your dogs barking problem. The collars cutting-edge bark-detection microphone can be adjusted to recognize your dogs unique bark so that no other sound can set off the unit. This collar is most effective when used on small dogs. Lightweight 28 g (1 oz.) collar Adjustable sound for pet sensitivity Uses PetSafe RFA-67 battery (included) Instructions and packaging in EN/FR/NL/ES/IT/DE