Aftermarket Buick, Pontiac, Olds GBody Radiator overflow reservoir and Windshield washer reservoir set.
Radiator Overflow Reservoir
Note: All B.O.P. are the same. GM only makes 2 units. They may not be 100% identical to what you had in the 80's. The Buick unit shown is what B.O.P. G-Body vehicles use now from GM.
Replaces GM 25525470-25506641. Use these numbers for cross reference.
This is for the washer bottle and overflow resevoir WITHOUT the cap. Please see the other listing to include caps.