Designed for dogs over 8 pounds, the Radio Systems PBC00-12104 Anti-Barking Deluxe Citronella helps to reduce nuisance barking. When the in-built sound sensor detects your dog"s bark, it gets activated and releases harmless citronella which interrupts barking. Your dog is eventually conditioned to stop barking. A safe and effective control, it features two manually adjustable levels of spray correction. The receiver collar is ergonomically designed to fit well with a quick-release buckle. Stain free, hypoallergenic spray is safe and effective. Perfect for small and large breeds. Long and short spray settings and fluid level indicator. Operates with 3-volt CR2 battery. Lasts up to 10-50 sprays per refill.