Tank Tags are a part of the Petroliana category of collecting.
Porcelain or aluminum tags were to be attached to Gasoline and oil storage tanks and/or pumps. Many became station key holders for office and restrooms.
Most date from the 1940s through the 1970s.
This Quick Quarter Mile Horsepower Calculator is a great example of ephemera from the age of race car tuning before every single thing was taken over by on-board electronics and computers.
A mechanic/driver could learn a lot from a run down the pavement and this little cardboard dial.
See more of the letter Q by visiting ABC Wednesday at: http://abcwednesday-mrsnesbitt.blogspot.com/