ONE PERSON OPERATION DESIGN: Refill bottle can be held on the brake fluid reservoir. On the 1L waste oil extractor bottle, there is a the hanger which can hook on the engine hood and keep the bottle above the vehicle bleeder valve, also the trigger locker is helpful for hand-free when suck. And you do not need to tread the brake pedal again and again.  transparent hose is good for monitoring the work situation, with universal black tapered nipple for connecting caliper bleeder valve threads