What's up with that?

Q Why are some mailboxes painted green? Does the Post Office still use them? —Bill Singerman, Ravenswood

A The olive-green mailboxes aren’t for the public. Known as “drop boxes” or “relay boxes,” the receptacles are used internally by the U.S. Postal Service. Mail carriers with vehicle access drop off sacks of letters and packages to the locked boxes for pickup and delivery by a local-route carrier. “Some routes don’t have a vehicle or sometimes a vehicle may be unavailable for some reason,” says USPS Chicago district spokesman Mark Reynolds, who added the drop system has been in place “forever.” “If it’s a walking route and there’s more mail than the carrier can handle, that’s when you’ll see a relay box being used.” Postal carriers can work despite rain, sleet and gloom of night—but not if they’re weighed down with all your Zappos deliveries.

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