Replenishment Alerts enable you to manage your inventory in Amazon's fulfilment centres without needing to constantly monitor each listing. You can set the alert quantity for individual products or groups of products. When the listing's fulfillable quantity reaches your threshold, either in units or weeks-of-cover, we notify you by sending you a Replenishment Alert e-mail.
When you select an alert quantity for a given product, select a quantity based on your average sales and the time it takes to order and ship stock to a fulfilment centre. This will give you time to send in a shipment to our fulfilment centre before your inventory is depleted.