Need help to identify a brass plaque or tag potentially revolutionary war. New England Ocean find, musket balls, coins, pottery..

Hi folks, so I found this little brass tag or plaque on a beach in New England along with other items that all date to the early to mid 1700's. Ive detected the area for years and its pretty clear that some activity happened here. There is little to no modern trash contaminating the area so most of the stuff I find is pretty consistent to the same time period. This is the first time I have fond something with writing on it and would like some help figuring out what it means and what it was for. The brass tag reads " AMMUN. ROOM LIGHT BOXES". I figured the AMMUN. stands for ammunition, but no clue who Room Light Boxes means. My guess it its some kind of ammunition ID tag that went on a crate but not too sure. In the first picture I included a few of the other items I have found in the same spot where the tag was found to give some context, and dispel any ideas that this is some kind of modern key chain or something silly like that. lol. Would appreciate all the help I can get. THX!