Turn your ring stack into a smart one with the Oura Ring, now 15% off for Amazon Prime members. It tracks sleep, stress, activity, and more, and even includes your first month of membership free. Choose from several finishes. The 30-ounce Stanley Quencher is on sale at Amazon for Prime Day. You can get the color "Tigerlily Plum" for just $21.

For the first time ever, Oura Ring is marking down its latest iteration, the Oura Ring 4, for Prime Day. Men’s Health is sharing it so you can get a leg up on purchasing the ring at a discounted price. Oura Ring is keeping sale details on lock but anything off £500 is worth checking out.

If you're in the market for a reliable sleep tracking ring, but don't have the budget to splash out on the likes of Oura, the Amazon Prime Day sale is a great place to shop for more affordable alternatives, such as this FKGZJF Smart Ring available for just $69.98 at Amazon now.