by John & Henri Boggs.

Motometer Sales Disk Display Item.

A disk insert would be fitted to the back of the motometer picture.  Then, when viewed from the front, a customer could see how their chosen disk would look if fitted to a motometer.

This item would have been seen in many auto part stores at the start of the 1920's.  Notice the two Masonic disks that were for sale.  Now vary rare and much forgotten.