The 2-Year Extended Warranty applies exclusively to Smart Transfer Switch purchased through Jackery&';s official authorized channels in the United States. Smart Transfer Switch Extended Warranty Requirements: To enable customers to take advantage of the 2-Year Extended Warranty, the STS must be installed by a Jackery-recommended certified electrician or a customer-selected certified electrician. Activation Process: 1. Log in the Jackery Official Website and visit the activation portal: https://www.jackery.com/pages/activate-extended-warranty2. Submit the required information through the online activation form. 3. Await email confirmation of submission (within 5 business days).