The Dorman Heavy Duty Washer Fluid Reservoir Cap keeps your rig Ready for the Road Ahead , being designed to provide a tight and leak-free closure for the fluid reservoir. This cap serves as an easy, twist-on replacement for your cracked, leaking, or lost reservoir tank cap. Restore your truck into proper working condition with this aftermarket washer fluid reservoir cap that provides durability you can count on, saving you the cost of dealership prices. FleetPride is your First Click in Heavy Duty .