Impact Mfg, Eclamshell (ClearPack Engineering), and stockclamshells (Panic Plastics, Inc.) are three different manufacturers even though they are all located in California. Impact has plants in California, Mexico, China and Taiwan and they manufacture clamshells, blisters, trays and other stuff. stockclamshells also manufacture clamshells, blisters, trays and other stuff. Eclamshell only makes clamshells