Original U.S. WWII MkII M21 Inert Practice Pineapple Fragmentation Hand Grenade with M200A1 Fuze Martini-Henry Accessories which authorized the master to

which authorized the master to engage in offensive actions against the enemy

maybe a unit marking or something similar

just as balloons had been used during the Franco-Prussian War (1870–1871) and as far back as the Battle of Fleurus (1794) during the French Revolutionary Wars

The rear sight bed is marked:

Original U.S. WWII MkII M21 Inert Practice Pineapple Fragmentation Hand Grenade with M200A1 Fuze Martini-Henry Accessories which authorized the master toOriginal Item: Only One Available. Totally inert and demilitarized according to BATF guidelines with hollow body and inert fuse. This grenade cannot be converted to an explosive device and is not available for export. This is a nice inert practice example of the iconic U. S. fragmentation pineapple grenade issued during WWII. The Mk II was standardized in 1920 replacing the Mk I of 1917. It was phased out gradually, the U. S. Navy being the last