PRO Athertons Star Series Direct Mount Stem
This is the same stem used by the high flyin' Atherton family. Like the rest of the Star Series, this stem is definitely worthy of the PRO nameplate. It is CNC machined out of 7050 aluminum and uses 5mm Allen bolts throughout for added strength. The direct mount design fits Fox 40 and Rock Shox Boxxer fork crowns. The handlebar clamp is 31.8mm and the total weight is 125 grams.
As with anything that is both high-end and trusted with the important task of keeping your handlebars connected to the rest of your bike, be sure to follow the manufacturer's specified torque settings.