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 . 

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