This is the breakdown of the USMC 782 gear
M1961 Cartridge Belt
The cotton M1961 belt was an upgraded M1936 pistol belt with a snap fastener between each of the middle row eyelets designed to attach M1961 model M14 magazine pockets.
M1941 USMC Suspenders
The design goes back to WWII and it was basically issued unchanged until it was replaced in the late '60s by the M1967 system.
M1945 SHOULDER EQUIPMENT PADS
These where original designed for use with the Army M36 suspenders , but at the end of WWII they where not needed because of the Army switching over to the M1945 suspenders with biult in pads.
The USMC started issuing them to be used with the M1941 Suspenders to make the wear of the suspenders more comfortable.
Three Cell Grenade Pouch
Originally designed to carry 2 fragmentation grenades in each pouch , it was found that accidental detonation could be a problem so only one grenade was carried in each pouch instead.
Jungle First Aid Kit and M1942 First Aid
Early during the Vietnam War left over stocks from WWII were used by Marines , but these were then replaced by the 2nd Pattern kits specifically made for the USMC.
Sometimes Marines would add a WWII M1942 First Aid Kit to the bottom of the JFAK as a means to carry more bandages.
M1910 Canteen / Canteen Cover and Cup
The Marines used these for most of the Vietnam War , around 1967 more Marines start using the Army M56 Canteen and Cover however.
M1961 Ammunition Pouch
The M1961 Ammunition Pouch was used from the begining of the Vietnam War until around 1968.
Even tough it was designed to hold a single M14 Magazine , it was found that they could also be used to carry a magazine for the M16 rifle.
M6 and M7 bayonet
The M6 Bayonet was the standard issue bayonet for the M14 rifle. It was introduced in 1957 along with the M14 rifle.
The M7 Bayonet was the standard issue bayonet for the M16 rifle. It was introduced in 1964 with the M16 rifle.

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