 Olive drab versions of the padded wool jacket were issued to US Army jeep crews during the war, and plaid Pendletons became popular casual wear in America during the 1950s.From the 1930s onwards, truckers and mechanics wore a distinctive outfit comprising mechanic's cap, white T-shirt, bandana, boiler suit, checked shirt, leather coat, Pendleton jacket, double denim jacket, and blue jeans.The skipper cap in particular signified the truckers' link with the big seaports, from which imported goods were transported all over the country.