|Red mail box and green public phone.|
There are still public pay phones in Japan. Not sure why they are green, but they are large because the units themselves hold the cash.
"The majority of pay phones in Japan take coins and "Telephone Cards" Telephone cards can be purchased in almost all convenience stores, train station shops and many times the cards are also sold in a vending machine inside or near the telephone.
"To use the card, insert it into the card slot and simply place your call. The amount of current remaining units on the card is displayed on the phone. If your phone card has become empty during a phone call the phone will beep to let you know and then you have the option of inserting another phone card or coins. At the end of your phone call the phone card will always be returned, even if it is empty. The phone will also stamp a hole along a unit chart on top of the phone card to let you know approximately how many units are left. The hole will be stamped close to the number that best represents the remaining units." -