These were the end of the Mark1.
First stainless Mark gun made.
Came in the Standard Box with the Re-pop wood salt cod box that the very first standards were shipped in.
First "red" medallion since the death of Alex Sturm when the bird was changed from RED to BLACK.
… IIRC also think this was the first "William B Ruger" autographed gun. It was considered a Collectible which was interesting due to the fact WBR didn't care much for the collector.
They were a big deal at the time (early 80's) the prices went thru the roof initially on "Gun List", a newspaper like classifieds / Gun Broker of the time. After a few years the premium went away.
The Box and "Salt Cod" Wood Shipper are nice.