Nix Sweat Patch Refills include four single-use sweat patches to be used in conjunction with the Nix Biosensor reusable Pod before each new workout. The Sweat Patch sticks to the bicep via adhesive and is completely non-invasive. We recommend wearing a patch during a sweat-inducing workout, ideally running or cycling, lasting at least 45 minutes in duration. After your workout is complete, a post-workout summary in the Nix App provides intel that can help inform your hydration strategy going forward. Contains 4 sweat patches. Biosensor Pod NOT included (may be purchased in the Nix Hydration Biosensor). Sweat patches measure just under 2.75 inches in diameter. Made with medical grade, latex-free adhesive. Patch should be disposed of after each workout and should not be worn more than once, as this can lead to inaccurate data. Manufacturer: NixCountry of Manufacture: China