A revolving letter of credit is used for multiple shipments over a specified period, allowing the buyer to make multiple drawdowns up to a predetermined limit. This type of letter is useful for ongoing business relationships where there are frequent transactions between the buyer and the seller. An important part here is to realize each party has an ongoing, familiar relationship meaning there is a certain standard of higher trust involved. Revolving letters of credit simplify the payment process by eliminating the need to open a new credit for each shipment meaning they may be more convenient and efficient.