What they offer is a tool for RFI (Reverse Fluid Injection). This is NOT the MityVac type of thing - though it will do double duty as a vac source as well.
I found a refurbished unit on ebay at a good price so I jumped on it and waited patiently (not so much) for it to show up.
It finally arrived. I read the manual, tried it. First time with no experience took 20 minutes to do the job. It works by injecting fluid into the system at the lowest point (the bleeder valve), forcing the air up through the line and out the master cylinder reservoir.
Using the thing is simple. Open the reservoir, drain out the fluid (the tool can be used to accomplish this task too), prime the tool with brake fluid, open the bleeder, attach the feed from the tool, squeeze the handle repeatedly until the reservoir is full. Done. (Actually the steps for a dual disk system involve two more steps equally as simple.
So if you need to bleed or flush a brake system you might want to add one of these to your tool collection - it will handle brakes, ABS systems, and hydraulic clutches.