This device was designed in order to collect the correct proportions of hydrogen and oxygen from the electrolysis of water. Its unique design helps correct issues such as falling test tubes perched over unsteady electrodes and gases escaping due to poor alignment. Each device consists of the electrolysis unit, gas collection tubes and a clear polycarbonate tub. The device will attach to any 6-12 Volt DC power supply (not included) using the alligator clips on the unit's power leads. Includes activity guide and an instructional CD.