The product is voice-activated. At the 1st bark the product applies a short warning tone. If a 2nd bark occurs within 30 seconds a more intense tone is sounded along with a short mild shock. If your dog barks a 3rd time， both the tone and shock become more intense. This pattern is repeated through 6 correction levels. If your dog continues to bark through all 6 levels， the most intense sound and shock are applied after each bark until your dog stops for 30 seconds or more. After 30 seconds of quiet， the product automatically resets to the 1st tone only level of correction. When your dog forgets and bark again， the warning tone reminds your dog without immediately applying painful stimulus.For most dogs， it needs 7 to 14 days to take effect; for few dogs， it needs 4 to 6 weeks to take effect; for very few dogs， it needs longer time to take effect.Power: 23 A battery.Dimensions: 6.3 x 5.3 x 3 cm.Adjustable strap length: approx. 25 - 50 cm.With electric shock function， effective yet safe to the dog.1 X Shock collar.1 X Red Strap.1 X 23A battery.1 X Testing light.2 X Electrode.1 X User manual.