It features a 400-yard range, 2-hour rapid charge batteries and Dogtra’s reputation as the world’s finest e-collar. Now the unit can be expanded to train two dogs at once. System includes: one transmitter, one receiver collar, a battery charger and splitter cable and an owner's manual. Precise stimulation level (0-100) 400-yard range Nick', 'Constant' and non-stimulating pager LED battery life indicator Fully waterproof collar/receiver and water-resistant transmitter