For Humane Contain X-10 electronic fence, Power Pet electronic doors, Sound Barrier and Yard Barrier sonic fences and Radio Mat pet deterrent kits;No need for your dog to wear multiple collars; this one does it all;You can add as many RX-10 collars as you like to your Humane Contain X-10 electronic fence to contain any number of dogs;Extremely slim, lightweight waterproof collar is designed for maximum pet comfort;Rechargeable battery never needs replacement; recharges in about 3-hour