These Original Series artifacts were Screen Worn by Commodore Decker and Captain Tracey in the episodes titled "The Doomsday Machine" 1967 and "The Omega Glory" 1968.
This set of rank insignias are very rare costume accessories, as they were custom made for filming and only worn in these two episodes.
Both came directly from the Bill Theiss estate when his collection was sold at Butterfields & Butterfields.
Tantalus Colony Production Patch
From the estate of William Theiss