Presold helps merchants capture revenue from out-of-stock products. Add a customizable pre-order button to any product and automatically tag orders, hold fulfillment, and manage mixed carts. When products are restocked, send automatic back-in-stock email alerts to waitlist subscribers. Features include collection badges, inventory limits, Shopify Flow integration, Klaviyo and Mailchimp sync, and a built-in analytics dashboard to track preorder and restock performance.