Original Item: Only One Available. This is a well-used original U.S. Marine Corps M-1955 Fragmentation Protective Body Armor Vest in size Large, representing the scarce early or “first pattern” configuration without exterior pockets. Introduced in the mid-1950s and used extensively by Marines during the Vietnam War, the M-1955 combined overlapping rigid Doron plates with layers of ballistic nylon to provide protection primarily against shell and grenade fragments rather than direct rifle fire.

This example retains the characteristic early configuration with no sewn exterior utility pockets and does not appear to have been converted to the later pocketed pattern. The cotton outer shell exhibits honest service wear and localized damage but remains substantially complete.

After the Korean War, the M-1951 was improved based on operational experience. The improved vest was introduced in 1955 as "Vest, Armored M-1955". The name was later changed to "Armor, Body, Fragmentation Protective; Upper Torso; (W / Collar, M-1955)".

The M-1955 remained in service with the US Marine Corps and the US Navy until the PASGT (Personal Armor System, Ground Troops) was introduced in 1978.

The M-1955 consists of 13 layers of nylon fabric in the shoulder area. In the area below, the vest consists of 23 3 mm thick, approximately 135 × 135 mm large Doron plates, which are sewn into pockets in the vest in three overlapping rows (and also overlapping within the row).

The vest is made of water-repellent cotton fabric. The 3/4 collar contains six layers of nylon fabric. The vest opens at the front and is closed with a sturdy zipper. The zipper is positioned so that the panels slightly overlap when closed, and is marked CONMAR. Furthermore, it is covered with a flap that is closed with four snaps.

Over the right shoulder of the vest runs an approximately 45 cm long piece of rope sewn into cotton fabric, which is known as the "Rope Ridge". It prevents the strap of a slung rifle from slipping off the rather smooth shoulder of the vest. As this is the first pattern, there are no pockets. There is some minor damage to the thin covering material but overall this example has held up well.

The tag on the interior reads:

IMPORTANT
ARMOR, BODY, FRAGMENTATION, PROTECTIVE: UPPER TORSO,
M-1955 (W/ COLLAR)
SEVENTY PERCENT of all combat casualties are caused by fragmentation type weapons. This vest, including the flexible shoulder pad area and collar, will afford you considerable protection from these missiles. However, it will NOT protect you from ALL small arms fire at close range. Take care of your vest and wear it wisely.

IT MAY SAVE YOUR LIFE!
U.S. MARINE CORPS.
SIZE L

The US Marine Corps placed a much greater emphasis on soldiers in the field wearing their vests than was the case with the US Army. Personal carrying equipment (M-1961 or M1956) was usually worn under the vest; this was easier because the M-1955 is shorter than the US Army counterparts ( M-1952 and M-69).

The vest is heavy and rattles a little, but does not retain body heat as much as the US Army nylon vests. It's more comfortable to wear than the M-69 because its collar is lower and doesn't restrict head movement as much.

The Marine Corps placed considerable emphasis on the use of fragmentation armor during the Vietnam War, and the M-1955 became one of the most recognizable pieces of Marine field equipment of the conflict. It remained in use for many years after Vietnam before newer body-armor systems gradually replaced it.

This Size Large example is particularly desirable for its early no-pocket configuration, surviving CONMAR zipper, distinctive right-shoulder rope ridge, original instructional label, and well-used field appearance. The combination of ballistic nylon and approximately 25 overlapping Doron plates illustrates the very different approach the Marine Corps took to fragmentation protection compared with contemporary Army soft vests. Preserved without later pocket conversion, it is a strong representative example of the M-1955 pattern worn by Marines during the Vietnam War.