Magene S3+ Cadence/Speed Sensor for Cycling, Bluetooth/ANT+ Bicycle Cadence Sensor Bike Speed Sensor, Wireless RPM Sensor Compatible with Android/Iphone and Bike Computer by Amazon.co.uk

• [Battery] Remove the insulating sheet of the pre-installed battery before usage; re-install the battery to switch between the speed and cadence mode.

• [Mode] 1 sensor can ONLY select one mode (Speed or Cadence) at the one time.So you need 2 sensors to test both speed and cadence.(1 for speed,1 for cadence)

• [Device] When using the Bluetooth protocol 1 sensor can ONLY connect to 1 APP or device concurrently; When using ANT+ protocol it can be connected to multiple devices at the same time.

• [Connection] When using a smart phone APP, you need to search for the sensor in the APP, searching through the phone system\u2019s Bluetooth setting is invalid.

• [Hibernation] S3+ sensor will automatically enter the sleep state for 1 minute to save power after the sensor is stationary, the sensor will ONLY start sending broadcasts after it is properly woken-up.