<P> In 1971 the United States Postal Service changed mail collection boxes to the current USPS Dark Blue with contrasting lettering . The coming of the automobile also influenced U.S. mailbox design , and in the late 1930s , an extension chute or `` snorkel '' to drive - up curbside collection boxes was adopted . </P>
<P> In 1971 the United States Postal Service changed mail collection boxes to the current USPS Dark Blue with contrasting lettering . The coming of the automobile also influenced U.S. mailbox design , and in the late 1930s , an extension chute or `` snorkel '' to drive - up curbside collection boxes was adopted . </P>
what are the blue boxes at the post office
what are the blue boxes at the post office
mail collection boxes
mail collection boxes