This power brake bleeder is designed as a one-person operation with no external power source needed. Because of the two-quart container, you can flush a complete brake system without having to stop to refill the fluid supply container. They say you should flush your brake system once a year due to the absorption of up to 2% moisture and contaminants, which will rust, corrode and wear-out brake system components. The "Power Bleeder" makes this an easy operation and it is a durable tool that is inexpensive to boot. Comes complete with the correct adapters, hoses and clamps.