We are guessing as to the date for this card gauge. It might be anywhere from the 1950's to the 1990's. The "Centre for Computing History" in the UK sets the date at 1960.¹

This card gauge was made by IBM and was used to check the accuracy of the card punching machinery used by those who stored their information on IBM cards (and that would be just about everybody!!). While many people today are not familiar with IBM cards...they were the go to storage medium for most of the world in the mid-20th century.

For more information on the history of the IBM card, click here to see our pages on Herman Hollerith and the 1890 census.

The reverse side of the card gauge has a sticker with instructions on how it should be used. The instruction label on this gauge is especially well preserved. The gauge is made of heavy gauge aluminum and measures 3 15/16" by 8 3/16".