Fulcrum Racing 5 Wheelset - 700 QR x 100/130mm Rim Brake HG 11 BLK ClincherAsymmetric alloy rims are laced to alloy hubs with sealed cartridge bearings via double butted steel spokes."Two To One" spoke ratio increase torsional rigidity by utilizing two spokes to carry out the function of one; slackening and torsion are limited increasing power transfer. Spoke tensions are more balanced and evenly distributed between drive and non drive sides increasing fatigue life Dynamic Balance rims weight the rim opposite the valve stem