How to choose which Apple Watch to buy

Due to a patent dispute with Masimo, new Apple Watch Series 9, 10, and Ultra 2 units in the US no longer have the blood oxygen feature, indicated by part numbers ending in LW/A. Older models are unaffected. With the release of the Series 10, discounted older versions are available, and refurbished options may also be found. The latest watchOS 11 does not support Series 4, 5, and first-gen SE models, so consider your needs and preferences when choosing the right Apple Watch for you.

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