This remote trainer is designed with safety in mind, featuring a maximum stimulation setting and lock and set to protect against accidental overstimulation. It has a 1/2 mile range and is loaded with unique features, making it one of the most humane and effective dog trainer collars. The transmitter is small and easy to operate, providing stealth operation when needed. The receiver is 2" x 1.5" x 1" and weighs 2.4 ounces, but still provides plenty of stimulation for most dogs.