Harley-Davidson began offering oil for sale to its customers beginning in 1909 and continues to do so today. Over the years, oil has come in a variety of containers and shipping configurations. During World War II, Harley-Davidson responded to the steel shortage by shipping oil in glass containers. This was one of many methods Harley-Davidson employed to aid in the war effort. After the war, Harley returned to using metal containers for its oil.