Check out http://www.928.cc/Brakes.htm#Power Bleeder.

Seems like a good price. When I asked if it will fit an MB reservoir, which I know it will, they said they only sell this product to Porsche owners at this time. Someone on the forum graciously offered his 928 VIN. I say we all buy one and reference the same VIN

http://www.motiveproducts.com/ is the manufacturer who offers the same thing for $5 more.

Sixto
91 300SE
81 300SD