GARMIN SPEED SENSOR 2
As far as sensors go, The Garmin Speed Sensor 2 gives you everything you need for almost no hassle. It attaches directly to the hub or either wheel, and then you can set it up online with a compatible Garmin device.
FEATURES
- ANT+ connectivity and BLUETOOTH Low Energy technology let you sync to Garmin Connect and other training apps, compatible devices, and fitness equipment for better data when you ride indoors and outdoors
- Odometer feature tracks your distance
- No head unit required