We independently Assess all advisable products and services. For those who click links we provide, we could obtain payment. Apple Watch Series 9 has an innovative sensor that tracks your temperature while you sleep, so that you can see changes after a while.7 Cycle Tracking takes advantage of this knowledge https://allhealthmarket.com/product/aeahmarket/appleband/silicone-strap-for-apple-watch/breathable-sport-straps-silicone-sport-bands-design-for-apple-watch-series-8-7-6-5-4-3-2-1-se-soft-replacement-strap/