Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
fitbit products using purepulse technology have a heart rate tracking feature that may pose risks to users with certain health conditions . 

```
. OPTIONS: ['Contract by using' 'Limitation of liability' 'Arbitration'
 'Content removal' 'Unilateral change' 'Jurisdiction'
 'Unilateral termination' 'Choice of law' 'None'].