Able to pump 700mmHg of vacuum on stubborn surfaces with ease. I bought it to pump pipes for quenching, not for pumping breaks, so unfortunately I can't confirm its effectiveness when used as directed. This works very well for the small tubes (50mL volume) I'm working with, but I think some lubrication is needed to get the larger volumes up to 60mmHg. I would still say that a hand pump is better than an electric one because you can get a much stronger vacuum with a hand pump than even with aβ¦