Note: This O-Ring is only compatible with Peterbilt lever style fuel caps. One pair of viton replacement O-rings for Peterbilt fuel caps. Made of viton for improved longevity. Viton provides increased resistance to chemicals, and temperature. Designed to replace O-rings on Peterbilt️ lever style fuel caps #11-04859-100/200. Approximate dimensions = 4” diameter Approximate Net weight pair = 1 oz