This is an unusual piece which measures 6″ x 4″ has the fuze (Including driving bands) from an artillery shell and a deactivated small arms round. This round is larger than the round issued for the Mauser. It measures 3″ in length and 3/4″ in diameter at the bottom of the round. I would estimate it to be from 15-20MM. This may be a round used against tanks among other things. The base is steel and the entire arrangement is quite heavy. An impressive looking piece and while there is some light surface rust on the base, with a little TLC it would clean up quite nicely.