NOS SPI Strasmann HSS-Co Roughing Shell End Mill 10 Flute 4" x 2-1/4" x 1-1/4" 

HSS-Co 55-S3

Lead = 560mm

1-1/4" Bore

10 Flute
4" x 2-1/4"

These were stacked in small bundles and taped together separated by cardboard. The outer unit has a light coating of grime / rust on the back side as seen in pics. It wipes off with a damp paper towel and a little rubbing.