I purchase in hopes of not calling my wife for assistance, but I had to and return to my 5$ bleed set. The hose and nipple were too big for my mercedes CLK 320 bleed valve, which gave a constant bubble reading(air in the line). That being said, I wasted a liter of mercedes brake fluid which is not cheap. I had to revert to my five (5$) bleeding set and the assistance of my wife, which works perfectly. I would suggest that they add different sizes (diameter in hose) and a smaller nipple cover than nipple (C). The concept is great. I wasted my fluid which if the reflection of the ratings. I will return this item!