Stans No Tubes Tubeless Valve Stems Schrader Valve - 32mm | Bicycle Tubeless TechnologyCompatible with straight valve hole Hugo 52 rims and designed to fit 7.5 - 8.5mm valve holes. Sold as a pair.Identifying your Hugo rim and selecting the correct valve stem:Stepped Hugo rims have a larger diameter valve hole on the interior of the rim, and a narrower hole on outside of the rim.Quick Tip: Dont remove your tire if you dont have to. If your Hugo rim decal reads:MAX RIM PRESSURE: 2.8 tires: 26psi, 3.0 tires: 24psiERD 615, 622x49.9, 29 in x 52.