It’s a Vintage List Finder Push Button Address Book!
This is a vintage metal push button telephone index that is in good vintage condition with a few paint specks. Just slide the indicator to the letter you want and then push the button and the directory for that letter will appear. Case has decorative gold swirl on front with alphabet running along edge. There are 4 protective feet on bottom of case. Back is marked “Vanguard Model”. This was possibly manufactured by Rolodex because the inside indicates that card refills would have been ordered through Rolodex.