This is a very rare German 7.92mm nahpatrone round.  It is sub sonic and believed to

have been made for silenced rifles.  It has a green lacquered case head and case.  The

muzzle velocity was reported to be 275 meters/second.

On the headstamp, there is info about who made the case.  Other data was lost when the

round was separated from it's box.  The case maker was Finower Industrie GmbH, Finow,

Mark, secret code of cg,  the st+ means the case was made of steel, 43 means that it was

made in 1943 and the 1 means that it was part of the first delivery lot.