RT-EM810 Ice Tech E-bike rotors with built in speed sensor magnet providing consistent braking performance through energy controlUses revolutionary stainless steel / alloy 3-layer sandwich construction that manages heat while ridingThe clad steel / alloy / steel rotor construction allows heat generated from braking to radiate quickly through the aluminium core achieving surface temperature drops of around 50 deg C. When used with Ice Tech pads surface temperatures can drop from around 400 to 300 deg C, this provides great improvements in performance all roundIce Tech rotors achieve long pad life, less noise and less fade due to improved heat dispersionRotor houses the magnet necessary for speed sensor function on Shimano STEPS equipped E-bikes allowing frame clearance for wider tyresCompatible with E8000 / E6000 systems and for rear wheel use onlyRotors are durable lightweight and rigid, using the proven Shimano Center Lock system giving increased strength and security with an easy set-upPrecision cut and drilled braking surface improves pad clearing in muddy conditions while aiding cooling under high loadLarge alloy spider is a highly rigid and lightweight support for the rotor surfaceSuper polished braking surface gives excellent braking performance