Del. Code tit. 6 § 4310
Retail installment sales negotiated and entered into by mail or telephone without personal solicitation by a salesperson or other representative of the seller, where the seller's cash and deferred payment prices and other terms are clearly set forth in a catalog or other printed solicitation of business which is generally available to the public, may be made as hereinafter provided. All the provisions of this chapter shall apply to such sales except that the seller shall not be required to deliver a copy of the contract to the buyer as provided in § 4309 of this title, and if, when the proposed retail installment sale contract is received by the seller from the buyer, there are blank spaces to be filled in, the seller may insert in the appropriate blank spaces the amounts of money and other terms which are set forth in the seller's catalog which is then in effect. In lieu of the copy of the contract provided for in § 4309 of this title, the seller shall, within 15 days from the date of shipment of goods, furnish to the buyer a written statement of the items inserted in such blank spaces.
6 Del. C. § 4310