New SportDog Brand In Ground Fence Systems 100 Acre Capability Maroon Yellow Navy It features a "conforma stretch" shoulder Yellow Black Orange It features a "conforma stretch" shoulder strap which aids in comfort and mobility Nike Flex fabrics stretch with your body Fits dogs 10 pound And up Contain an unlimited number of dogs with additional collars (sdf r) Collar gives Tone (beep) and vibration (Buzz) warning before moving to one of four static stimulation levels (you choose the best level for your dog) Transmitter features wire break alarm and built in Lightning Protector Containment System Easy to install containment kit includes everything needed to cover 1 1 3 acres of land for one dog