World War I German 37 mm Spent Shell

This is a World War I era German 37 mm spent shell casing. This casing is in overall good condition, although there is some heavy rusting, patina, and some greening to portions of the shell. The base of the shell is marked as “C / 98.98, 1902, KARI SRUHE, 45 , 8.” Additionally, there is a small crown above a letter “M” at the top of the casing, and a pair of small markers underneath the “VIII” and “1902.”