Disposable emails let one shopper burn a promo 50 times, place fake orders, and drive chargebacks. Checkout Defense blocks them at checkout and on signup.A self-maintained list of 7,500+ disposable domains, refreshed weekly, runs checks locally — no third-party service. Toggle checkpoints, add allow or block domains. Risky signups are tagged for review.An added layer of store security, not a fraud-scoring or chargeback-prediction tool. Merchants remain responsible for order-review decisions.