There are two types of mold parts, ready-made standard parts and ETO (Engineered-to-Order) parts, the latter are of increasing importance to manufacturers. However, the ETO parts require more engineering support and communication than the ready-made standard parts. Existing e-Catalog modules provide classification structures of products that allow customers to select products based on their needs, and the trade begins with the provided specification. However, machine parts or mold parts have different purchasing patterns. Customers do not purchase the ready-made standard parts offered by an e-Catalog. They usually (1) add own options to the provided specifications or (2) change specification items such as length. To support these trades, a new e-Catalog system is proposed. The proposed system is based on the product design process and the specification selection process in addition to the parts classification structure.