Pair of Bofors 40mm MK2 AL0790 544 L/60 anti aircraft shells.
Both shells carry the Royal Marines badge.
Shell cases are manufactured by Lyon incorporated, Detroit, Michigan and then assembled “loaded” by triumph explosives inc, Elkon, Maryland.
Bofors shells are sometimes not date stamped due to the focus being on functionality & availability rather than detailed record keeping.
Measuring 31cm with 6cm diameter base