SportDOG Brand NoBark 6 - Waterproof Bark Control Collar with 6 Levels of Shock - No Programming Required This bark collar corrects barking by sending a static correction when it detects the vibration of your dog's vocal cords Using progressive correction, the collar starts at the lowest level of correction and automatically raises the level if your dog continues to bark; After 30 seconds of silence, the collar resets to the first level of correction again The SBC-6 is waterproof, fitting dogs 8 pounds or larger with neck sizes 5" - 22" Replaceable lithium batteries last 3-6 months; Features a low battery indicator to let you know when to change the battery The detailed operating guide and a locally based Customer Care Center, available 6 days a week, provide support when you need it By designing our products in the field, with heat, cold, rain, snow, dust, mud, and wind in mind, SportDOG has become the most recognized brand in the electronic tracking and training categories, making the promise to always create "Gear The Way You'd Design It"