Workers in the rubber heel manufacturing unit in Windsor Vermont in United States.

Manufacturing of rubber heels for the soles of US soldiers' boots at a Goodyear plant in Windsor, Vermont. Men and women emerge from rubber heel manufacturing facility in Windsor Vermont. Workers wash uncured rubber heels and keep them to dry so as to prevent them from sticking. Man puts rubber heels in molds for nailing. Each nailed heel passes through vulcanization machines. Woman checks the vulcanized rubber heels and puts them together. Women pass completed heels through an X-ray machine and check for defects. In Akron, Ohio, a US Army soldier stands in front of the statue of Charles Goodyear, the founder of Goodyear rubber company, and the discoverer of vulcanization.