Renthal Duo Stem The Renthal Duo stem reaches bicycling nirvana by being both light weight and very strong. You will notice that the Renthal Duo is horizontally divided and that allows Renthal to machine away material without compromising strength. Renthal uses CNC machined 6082 T6 aluminum and incorporates a U-shaped cradle clamp to eliminate handlebar stress risers that can be found with traditional stems. This yields a package that weighs 143 grams (including bolts) and will stand up to the punishment your riding will dish out. 50mm 10 degree rise 143g 31. 8mm handlebar clamp | Renthal | Duo Stem 40Mm Length | Aluminum