I assume this was inserted in quarts (like plastic discs that Gulf used) to be found by the attendant when he added oil to a customers car. He would then remove from the can or funnel and redeem towards a gift or promotion from the company. The incentive was for the attendants to ask customers if they could check the oil, and then sell/add the quart(s) right there at the pump.

Anyone have any similar ones from other oil companies?

I have these from Marathon.
I remember when the red ones came out in the mid-1960's & they came in three colors, each color represented a prize amount.

Dave

That's a neat idea. Thanks for sharing!

Justice Brothers oil additive products still use this "reward token" promotional incentive inside many of their current products. John