[. . . ] Install the GSC10 Sensor Place the GSC10 on the rear chain stay (the side opposite of the drive train). [. . . ] The red LED blinks each time the crank arm passes the sensor, and the green LED blinks each time the wheel magnet passes the sensor arm. When everything is aligned and working correctly, tighten the cable ties, sensor arm, and spoke magnet. GSC10 pedal magnet sensor arm indication line For more information on using the GSC10 with your compatible GPS device, refer to your owner's manual. Configure Your GPS Device To activate the GSC10 accessory: 1. For example, on the EdgeTM 305, select Settings > System > Accessories. Note: To set up custom data fields on your GPS device to display cadence data, refer to your owner's manual. May 2006 190-00646-00 Rev. C Printed in Taiwan GSC10 TM speed and cadence sensor Sensor Pairing What is pairing?Pairing is the process of matching sensors, like your GSC10, with your compatible GPS device. This process occurs automatically when you turn on your GPS device and only takes a few seconds when the sensors are on and functioning correctly. Pairing tips: · Position your GPS device within 3 meters of the sensor while pairing. [. . . ] Use a coin to twist the cover back into place (arrow points battery to locked). [. . . ]