In mid 1943 this bayonet as made by UFH in USAwas ordered with shorter blade of 10 inches length, it was identical to the older 1905 pattern that it replaced, except for the longer blade.  A shorter USM7 olive drab metal and fiberglass scabbard came with it.  A very few were dated 1943 the majority of these are undated.

Below is an M1 Garand with bayonet attached. 

Below is an M4 bayonet made by IMPERIAL with a USM8A1 scabbard, this bayonet was usually attached and equipped with the  M1 .30 caliber carbine.  A total 2,260,519 of these M4 bayonets were made during its lifespan from July1944 to August 1945.

Below is the M1 carbine with bayonet fitted, it was a very versatile and lightweight weapon that saw action with the US army in all fronts of the European war.

 Below is the M1917 Remington bayonet with 17 inch long blade, designed for deadly use in the trenches of the first world War.  The bayonet could also parry up to the M1 Garand and M1903 rifle.

 During the Pacific campaign whilst fighting in the jungles of Okinawa and Iwo Jima, the US marines would leave their bayonets attached to their rifles most of the time.  Jungle warfare was such that an injured or suicide enthused Japanese soldier could come charging out of the bush and attack the marines face to face, so a bayonet could give them some assistance in close quarter battle.

As I said on one of my another bayonet web pages, a long bayonet effectively turned a soldiers rifle into a spear in the many hand to hand and close quarter battles that they endured.