RARE 1920s Chicago's Straus Building / Metropolitan Tower Observatory Ticket

Description

Great little piece of Chicago's history and American architecture history - rare ticket to Chicago's Straus Building Tower's 13th floor observation deck.
The Straus Building Tower, now called the Metropolitan Tower, was built in 1924 and was once Chicago's second largest building. The history of the observation deck is somewhat vague, but it was located on the 13th floor and offered a unique 360° view of Chicago. It doesn't appear like the observation deck was open to the public for a long time and probably why these tickets are scarce and likely from soon after the building opened - around 1924-1925.
This ticket also appears to be given as complimentary or invitation, rather than sold.
A lot about Straus' observation deck is a mystery so I hope this can inspire further exploration into one of Chicago's iconic buildings.
A very well-preserved ticket and approaching 100 years old too - free of stains, tears, and creases. Just a little wear on the edges and corners.
It's approximately 4-1/2" x 2-1/2" and kind of feels like it's made of a thicker rag stock material.