Bias ply tires are a type of tire construction where the layers of fabric, known as plies, are arranged diagonally. This design allows the plies to cross each other at angles, typically around 30 to 40 degrees. Bias ply tires are known for their flexibility and comfort, making them suitable for certain types of vehicles, especially classic cars and some off-road applications. These tires generally provide a softer ride due to their construction, but they may not handle as well at high speeds compared to radial tires. Bias ply tires are often used in vintage racing and for classic cars, where authenticity and a specific driving feel are desired.