I am selling this item because I have no opportunity to use it after purchase. It is a new, unused item, but it has been stored personally, so there may be some damage to the box. Please be aware of this beforehand. A sensor that allows direct speed and cadence measurement from the wheels and crank by connecting to a GPS cycle computer. Compliant with Bluetooth Smart standards, it can be used with all GPS computers. The sensor arm has a wide range of adjustment. Magnets included. SPEC ■ Color: BLACK ■ Battery: CR2032 button battery x 1 ■ Weight: 26g (magnet 6g)