While most other manufacturers cast or forge their bottom bracket tools, we machine ours for greater precision. Whenever you're dealing with anodized surfaces, great care needs to be taken to keep those surfaces from getting marred, gouged, and stripped out. That can be nearly impossible with some spanner style tools, and difficult with other loose-fitting sockets.
The most unique feature about this tool is the inner nub; that nub in the center of the tool is the same size as the crank spindle. What this does is give you a second point of contact that keeps the tool from coming off of the part when trying to remove stubborn cups.
This dual sided socket is designed to work with the new Shimano DA-9000/XTR-BB93 bottom bracket as well 6800 Ultegra and 5800 105 11spd groups (BBR-60).