The standard American penny has a purpose greater than decking out your classic loafers. You can check your tire tread using an inverted one-cent piece.

Federal law and common sense say your tread cannot be thinner than 2/16 inches. At that thickness, tires cannot effectively grip blacktop around sharp curves or through deep water – you’re just asking to hydroplane. Thin tread also quickly can turn into shredded tread. Bubbles and bursts result when there is not enough rubber to contain 35 to 42 pounds of pressure per square inch.

As it turns out, the space between the top of Honest Abe’s head and the edge of the coin equals exactly 2/16.

To check your tread, stick the inverted penny into your tire treads. and hold it up against the tread wall.

If our 16th president’s head is wholly visible, stop what you’re doing and prioritize new tires. Forty Fort Lube can replace your car’s tires and have them installed by our trained technicians.

If the tread wall covers part of Lincoln’s head, you’ve got some time. The Car Care Council recommends performing this home test once every month.