SHIMANO WH-6700 Ultegra Tubeless Clincher Wheelset 6061 aluminum alloy rims deliver a super-lightweight and aerodynamic ride without compromising strength and stiffness Wide flange hub and offset 23mm front rim for high rigidity and power transfer Digital adjustment system is easy to adjust and reduces QR axial force Cup and cone bearings for low maintenance and best performance 16/20 stainless steel, bladed, double butted spokes for strength and speed