Educator E-Collar Humane Dog Training Collar with Remote, 100 Safe Tapping Stimulation Levels, Night Light, Waterproof, Rechargeable, 1/3 Mile 1 Small Dog, PurpleThe Micro ME 300 one dog system with 1 3 mile range, small receiver for small to medium sized dogs 10 pounds and up with neck size 5 to 22 1 2 inches Includes 1 Biothane dog collar (3 4" wide x 30" long), 1 ergonomic mini transmitter (2. 6" diameter x 1. 1" thick x 4. 5" high) and 1 RX 070 Micro receiver (1. 6" long x 1. 2" wide x . 8" high, 1. 9 oz.) smaller version of the Mini Educator receiver at approximately 20% smaller, 20% lighter and 20% less