The defining characteristic of 4 inch AC fans is their compact size, with the diameter of the fan blade assembly measuring approximately 4 inches (about 100 millimeters). This relatively small size makes them suitable for installation in confined spaces where larger fans would be impractical.

Despite their compact design, these fans are engineered to deliver sufficient airflow for cooling small devices or ventilating restricted areas. Their slim profile and lightweight construction also facilitate easy mounting and integration into various systems.

4 inch AC fans operate on alternating current power supplies, typically ranging from 110V to 240V depending on the model and regional standards. AC fans offer advantages in terms of simplicity and compatibility with standard electrical infrastructure without requiring additional converters or power conditioning.

The AC motor design is generally robust and reliable, suited for continuous operation in many industrial and commercial environments. This makes 4 inch AC fans a practical choice for applications requiring steady, uninterrupted airflow.

These fans are commonly manufactured with durable materials such as high-grade plastic or metal housings and blades. The choice of materials depends on the intended application environment. For example, plastic blades are often used in indoor or less demanding environments due to their lightweight and corrosion resistance, while metal blades may be preferred in harsher conditions for enhanced durability.

The construction quality influences noise levels, vibration, and overall fan lifespan, which are important considerations in sensitive applications such as electronics cooling.

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The 120×120×25mm 4 Inch AC12025 AC Axial Fan is a high-performance cooling fan commonly used in computer cases, power supplies, and other electronic devices that require efficient heat dissipation. It features a compact size that makes it suitable for both small and medium-sized applications.
This fan is designed to deliver a strong airflow with a low noise level, ensuring effective cooling while maintaining a quiet environment. It uses an AC motor which provides consistent and reliable operation.