Body bag

The body bag was intended to be an object included in Halo 3. However, Bungie scrapped the idea, possibly due to unnecessary details or moral conflicts. Its purpose was to hold deceased Marines. Analyzing the image of the body bag, one can observe a Marathon symbol among the various details printed on the bag in the top, right corner of the bag.

Trivia
The "Body bag" has the UNSC insignia on it, as well as the soldier's serial number, rank, and date in which he/she has died.