This is the best, most humane bark-busting collar on the market! When the collar's sensors pick up a bark, it sprays citronella in front of your dog's nose, which distracts him from barking. This collar works—it stops nuisance barking in 88% of the dogs tested. Sensors will only pick up barking from the dog wearing the collar. Safe for dogs from 6 to 160 lbs. In black. Collar kit includes adjustable nylon collar with oil reservoir for 25 sprays, 3-oz. (250-spray) filler bottle, 6-volt alkaline battery, training materials, and instructions.