Amazon return- tested an works Barrier 1'6" to 8'6" CO-Z Pet Barrier and Collar, Indoor Adjustable Dog Barrier Transmitter & Waterproof USB Rechargeable Dog Training Collar, Wireless Fence Barrier,1'6" to 8'6" Range ADJUSTABLE & WATERPROOF COLLAR: Three metal prongs (0.8/1.1/1.9 cm long) and a training collar that adjusts from 6 to 17 inches in width come included to fit most adult dogs