Description: 【Type:】 The Car Thermostatic Gauge Radiator Cap water tank cover with temperature gauge meter is not only to prevent the water tank from leaking, but also to adjust the pressure balance of the water tank and maintain the water level balance of the water tank; 【Function】 As the water temperature rises, the cooling water begins to expand. Once the pressure relief value is exceeded, the water tank cover will spring open, and the cooling water will flow to the auxiliary water tank for storage; Conversely, when the water temperature drops, the volume of the water becomes smaller, and a vacuum is formed inside the water tank At this time, the water tank cover will also open to suck the water from the auxiliary tank back into the water tank to keep the water level balanced. 【2 in1】 Car Thermost Radiator Cap Cover with Water Temp Gauge Meter Combines a radiator cap with a temperature gauge. Durable Material : 【Durable Material】 Thermost Radiator Cap Cover With Water Temp Gauge is made of ABS plastic and aluminum alloy material for strength and durability. 【Size】9.6cmx16.5cmx4.5cm/3.78inchx6.50inchx1.77inch, compact size, direct installation. Specification: Material : ABS Plastic Aluminum Alloy Size Chart: 9.6cmx16.5cmx4.5cm/3.78inchx6.50inchx1.77inch  Package Includes: 1 Car Thermostatic Gauge Radiator Cap Note: Please allow slightly errors due to manual measurement and different monitors.