The BL-100 is the most advanced anti-barking e-collar on the market. It utilizes digital processing technology to distinguish your dogs bark from other sounds, therefore preventing any chance of an unintended correction. For customers who wish to allow some barking can adjust it to the auto-mode function, which allows some barking. It adjusts the correction level automatically to increase and decrease based on the dogs barking behavior. This product is assembled and tested in the USA. 100% Guaranteed to Work. No Questions Asked Return Policy.