Bontrager's Interchange ANT+ Combo sensor is a speed/cadence sensor in one. It includes a 5mm crank cadence band magnet, aero wheel magnet and a silicone mounting strap to fit most chainstays. It wirelessly transmits your data to a variety of ANT+ enabled receiving devices including Bontrager Node computers (sold separately). Installation is a snap, too.
Compatible with Bontrager's Node computers and many other ANT+ devices.