Mavic Open Pro 21 UST Road RimThis road bike rim features a robust maxtal aluminium construction, which allows it to provide a higher strength to weight ratio when compared to a traditional alloy rim. Mavic has also equipped it with a 19mm inner rim width, so riders can enjoy a wider and more comfortable roll on the road. Thanks to its UST tubeless-ready technology, this model allows for tubeless tyres to easily be mounted for benefitting from lower rolling resistance and greater traction, with less chances of flats or punctures. Compatible with rim brakes, this version is a great choice of upgrade for riders who want to enjoy dependable braking from its precisely CNC-machined UB Control brake track surface. One final highlight is its updated rim bed shape, which improves the mounting of any tyres, tubeless or tube-type.Features: Material: Maxtal Aluminium Use: Road Size: 700c ETRTO: 622x19TC Hole Count: 32 hole Inner Rim Width: 19mm Spoke Bed Diameter (ERD): 589mm Tubeless Ready: Yes, UST compliant (Mavic UST valve recommended - not supplied with the rim) Brake Compatibility: Rim brake Recommended Tyre Sizes: 25 to 47mm Recommended Nipple Length: 12mm Valve Hole-Diameter: 6.5mm Drilling: Traditional Rim Tape or Valve Included: No, available separately Low profile SUP/Welded Single eyelet Single or Pair: Single Manufacturer's Part Number: LJ4240100 Weight: 430gTechnologies: SUP (Soudé Usiné Process): Stronger and smoother joint. After bending, the rim joint is arc welded. The welded seam is then milled for a smooth finish. UB Control Brake Track: The braking surfaces are precisely CNC-machined. UST Tubeless Ready: The UST concept improves traction, control and comfort while reducing inertia and flats. The tubeless-ready construction results in a lighter tyre for improved performance. Maxtal: Light and strong. Exclusive to Mavic, this specific aluminium alloy offers a higher strength to weight ratio than conventional 6106 alloy.Buy Mavic Wheels & Tyres from Chain Reaction Cycles, the World's Largest Online Bike Store.