S3+ stride sensor comes in black with a new, firm shoe attachment which guarantees accurate speed and distance measurement. This small and lightweight sensor measures each stride you take, helping you analyze the effectiveness and efficiency of your run.
Measures running speed/pace and distance
Helps improve running technique by telling your running cadence and stride length
Determines your Running Index, which tells you about your running performance
Shock and water resistant, handling even the most demanding runs
For Polar RCX5; Polar RCX3; Polar RC3 GPS ir Polar RS800CX.