Purchasing stock clamshells eliminates design costs and reduces lead times. Purchasing from the stock supply also reduces storage space requirements and reduces inventory. VisiPak also offers full custom design services. One option, called the Eco-Shell™, is a cross between a stock and a custom clamshell. The thermoform manufacturing process allows an existing stock mold to be modified with secondary tooling. Using this option, the only design cost encountered is for the secondary tooling, creating a low cost custom designed package.