Vintage Russwin Mounted Salesman's Sample Dummy Deadbolt with cover

I believe this one is a Russwin, because it was with several other identified Russwin knobs.

Deadbolt is mounted on a block, front plate with rotating cover only 

Block is approximately 4" X 4"

Nice vintage patina

Block has CYL. COL. A3580 FIN 13 stamped on the block

Vintage sample block in good condition.  Some corrosion on the lock and wear to the block.