PetSafe PIF00-12917 2-Dog Stay and Play Wireless Dog Fence System Lightweight, portable wireless transmitter - No Wire to Bury (2 Collars) Creates an adjustable circular perimeter of up to 3/4 of an acre anywhere you go Rechargeable receiver collar charges in 2 to 3-hour and is ergonomically designed for comfort Offers 5 levels of static correction plus a tone-only mode for training of dogs over 5-pound with neck sizes 6 to 23-inch Free Shipping in the United States!