ZIPCODE

Group of digits on a US letter (3,4)

Solution has appeared in 2 crosswords (2 across and 0 down):

• Quick crossword No 15,791 — 2020-12-16 00:00:19
  9A: US mail identification symbols (3,4)
• Quick crossword No 15,422 — 2019-10-10 23:00:35
  22A: Group of digits on a US letter (3,4)