Splitting parts down the middle isn't usually a great way to make them stronger, but Renthal's Duo Stem isn't your usual bike part. Renthal's motocross background gives it a different perspective than most MTB part manufacturers, so maybe the uniqueness of the Duo shouldn't be surprising. By crafting it from two parts of CNC machined 6082 aluminum, Renthal was able slim the weight down to a weensie 124g without any loss of strength compared to more traditional stems. Slap it on your 31. 8mm diameter bars and get to rippin'.