Function and benefits: The windshield washer tank cap keeps the wiper system clean by preventing dirt and moisture from entering the reservoir, ensuring the washer fluid remains clean and the wipers operate normally. Sealing performance: The plastic cap tightly seals the reservoir opening, providing strong sealing to prevent washer fluid leaks or evaporation and to support a stable, longlasting wiping effect. Material and durability: Made from automotivegrade plastic, the cap is tougher and designed to remain in good condition after longterm use. The smooth surface allows easy cleaning and lowmaintenance upkeep. Easy installation: The clipon design enables quick replacement of worn or damaged caps without the need for tools. Compatibility note: The compatibility list on the product details page is for reference only. It is recommended to check the OE number before placing an . Use scenarios: Replacing a worn or damaged cap on a windshield washer fluid reservoir in a car, SUV, or light truck to restore proper sealing and prevent leaks. In dusty or humid environments, where keeping the reservoir sealed helps maintain fluid quality and prevent contamination. During routine refilling and maintenance, to ensure a secure, drip seal that protects washer fluid from evaporation.