Border Patrol Travel Documents, Part 3
INS forms I-151 and I-551 are issued to aliens who
have been granted permanent resident status in the United States.
They retain this status while in this country. The bearer is required
to have this card in their possession at all times.
The first Alien Registration Receipt Card, form
I-151, was introduced in 1946. Through 18 years of various revisions,
it remained green in color. It became known as a "Green Card".
This term is still commonly used, although the cards have not
been green since 1959. These "green" cards contained
no expiration date and were only required to be renewed if the
recipient was under the age of 14 at the time of issuance, or
if the card was lost or stolen.