Approx.  1.75" inside diameter..2" outside diameter...
The product is a vintage fuel cap with a white ceramic insert that features the inscription "Buy Clean Fuel - Keep it Clean." This item likely serves as a reminder to users to purchase and use clean fuel for their heavy equipment to ensure optimal performance and efficiency. The vintage design adds a unique and retro touch to the product, making it a distinct and eye-catching accessory for any heavy equipment owner or operator.

D5 HOLLY