2PCS Engine Coolant Reservoir Tank with Black Radiator Cap Replacement for OEM 21712 79900 Coolant Overflow Expansion Bottle Engine Radiator Cooling System Tank Universal Coolant Reservoir








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Color: Black
Features
- MATERIAL & DURABILITY: Made of thickened plastic for better pressure resistance and heat tolerance; designed to perform well in demanding engine radiator environments; built to reduce cracking and leakage
- FUNCTIONAL DESIGN: This coolant reservoir tank supports proper coolant overflow and recirculation; helps stabilize system pressure; maintains consistent function of the radiator cooling system
- EASY INSTALLATION: Direct fit replacement for OEM 21712 79900; ideal for quick swaps in repair or maintenance tasks; please confirm compatibility with your vehicle before purchase
- CAP PERFORMANCE: Includes a tightly sealed yellow radiator cap to help reduce coolant vapor loss; built to handle temperature fluctuations; ensures secure fit on the expansion bottle
- APPLICATION & USAGE: Designed to manage coolant levels and reduce overheating risk in standard automotive cooling systems; works as a practical engine coolant refill or upgrade part
Description
This 2-piece engine radiator coolant reservoir tank set features a direct replacement design that supports optimal coolant overflow management and helps maintain stable engine temperatures. Each tank includes a yellow coolant reservoir cap, closely replicating OEM 21712-79900 specifications for reliable compatibility and performance.Crafted from durable, heat-resistant plastic, the tanks are built to endure high operating temperatures, resist deformation under pressure, and ensure long-lasting functionality. The high-strength material construction provides a leak- resistant structure, ideal for vehicle cooling systems that demand consistent pressure control.This product is designed for vehicles equipped with an external coolant reservoir system and is used to replace worn or cracked expansion bottles. It helps prevent coolant loss due to overflow, maintaining the correct fluid level in the system during engine operation. The snap-on cap with precision fit ensures secure sealing and easy removal when needed.Each tank measures approximately 1.5 x 1.5 inches (outer diameter), with an inner diameter of 1.2 x 1.2 inches and a height of 0.43 inches. The compact size allows seamless integration into tight engine bays while maintaining original system performance.Compatible with cooling systems that require an external tank and top-mounted cap matching OEM part number 21712-79900, this set provides a cost-effective solution for radiator maintenance. It is recommended to verify the part number and dimensions before purchase to ensure a proper fit.Whether you're replacing a damaged tank or performing scheduled maintenance, this coolant overflow tank set offers dependable performance and straightforward installation, helping to extend the life of your engine cooling system.
Brand: ONISMEZ
Color: Black
Material: Plastic, Rubber
Exterior Finish: Plastic
Item dimensions L x W x H: 1.85 x 1.85 x 0.18 inches
Brand: ONISMEZ
Color: Black
Material: Plastic, Rubber
Exterior Finish: Plastic
Item dimensions L x W x H: 1.85 x 1.85 x 0.18 inches
Vehicle Service Type: Van, Car, Suv, Truck
Item Weight: 2 Ounces
Closure Type: Screw-on, Pressure Release
Automotive Fit Type: Universal Fit
Manufacturer: ONISMEZ
Style: Standard
Model: Coolant Reservoir Cap
Item Weight: 2 ounces
Product Dimensions: 1.85 x 1.85 x 0.18 inches
Country of Origin: China
Item model number: CRC0320
Manufacturer Part Number: ONISMEZSGF03257
Date First Available: March 20, 2025
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