Sierra Silverado 4000 5/16" Fuel LineThe Silverado 4000 fuel line is the best B1 fuel line in the market place. The Silverado hose has a small O.D., is extremely flexible and easy to clamp. Fuel Line is resistant to ethanol blended fuels and the gray color keeps hose cooler and helps prevent vapor lock. For strength and a weather and UV resistant CPE cover, Polyester reinforcement has it covered.Features: THV500 barrier layer - prevents permeation; Nitrile jacket ; Polyester reinforcement; CPE cover; EPA and CARB compliant; Specifications:I.D.: 5/16" or 7.9mm; O.D.: 1/2" or 12.75mm; Wt. "C": 7For above deck primer bulb applications, and is not fire retardant.