A blanket sales order is a type of master order that contains specific quantities for certain inventory items at pre-determined prices that the customer can draw against over a set period of time.

Your customer commits to purchasing a large quantity which can qualify them for volume discounts within the agreed period of time
The pricing is set over the course of the blanket contract, which eliminated the possibility of pricing fluctuations
Eliminates cash tie ups induced by holding stock in a warehouse by allowing your customer to have a product shipped to them when they need it
Because you know what your customer needs and when they need it delivered, you know what to manufacture and when
They help your company reduce the amount of cash tied up in raw materials and components, while allowing you to schedule the resources needed to manufacture the product