Here is ASCII art of the kanji for "yon" (the Japanese word for four(4):

@@@@@@@@@@
@  @  @  @
@  @  @  @
@  @  @  @
@  @  @  @
@ @    @@@
@@       @
@@@@@@@@@@

The same character is used for "shi" in the sense of the number 4. So, for instance, the date April 4, read "shigatsu yokka", would use this character twice.