Prestone AS245 Bug Wash Concentrate Citrus Windshield Washer Fluid Additive - 15.5 oz. Helps improve ordinary washer fluid performance to remove stubborn bug residue, road grime, bird droppings, and tree sap Specially formulated to add directly to your windshield washer reservoir Penetrates biological deposits to break down and emulsify them The formula digests the deposits so they are easily removed from the windshield by the washer fluid and wipers