By the 1930s, Hazel-Atlas had fifteen plants (plants included those in Clarksburg, WV; Zanesville, OH; Ada, OK; Montgomery, AL; Oakland, CA; Pomona, CA and other locations) and was the largest glass manufacturer in the world. Hazel-Atlas manufactured tremendous quantities of "depression" pressed glassware in a wide variety of patterns throughout the 1920s, '30s and '40s. They also produced many of the white milkglass "inserts" used inside zinc fruit jar lids, as well as many types of milkglass cold cream jars and salve containers. Also an important maker of a very large variety of bottles and jars for the commercial packaging industry. "Atlas" was the name brand of their most popular line of fruit jars for home canning. Hazel-Atlas, at that time the third largest producer of glass containers in the U.S.,became a subsidiary of the Continental Can Company in 1957.