Model Number: HC1265B Key Specifications/Special Features: Features1. With battery charging circuit, energy-saving design, and automatically self-protective features.2. Not being easily disturbed by other noises.3. Model L is suitable for most middle-large size dogs, and Model S is for most middle-small size dogs.4. Switch: Press the button shortly to turn on and continuously press one second to turn off.How to Use1. PD 258 sensitivity can be adjusted, and the users can adjust it according to the dogs barking noise.2. The sensitivity can easily be adjusted with five levels, and the default level is three. Press "+/-" button, it will "bleep", and the higher the sensibility, the easier it works.3. Static test: put the white test lamp on the two electrodes of the anti-bark collar, and then blow into the sensor located in the middle or simulate loud dog barking, after the anti-bark collar works third times, the test lamp will gleam.