1. The film material is obviously different.
For film capacitors, the costliest thing is the film raw materials. The quality and price of film capacitors produced by large companies and small companies vary greatly. In order to reduce costs, some manufacturers will definitely choose low-quality films with lower prices. Uneven plating, burrs, or direct purchase of defective products produced by metal film manufacturers, using inferior films, the quality of the produced film capacitors will definitely be poor.

2. The difference of gold spraying.
The gold spraying of film capacitors should use five-element alloys or six-element alloys, so as to ensure the electrical properties of the capacitors. In order to save costs, inferior film capacitors will use pure zinc sprayed with gold. Although the cost becomes lower, the probability of capacitor quality problems increases.

3. The difference of CP line.
Inferior CP lines, the main problems are that the wire diameter is not enough, just like the principle of cutting corners in building steel bars to make the CP line thinner. At the same time, low-quality CP wires also have the problem of low tin and copper content, which leads to poor soldering of capacitors, easy solder joints, and poor over-current capability.

4. The difference of rated voltage.
In order to fight the price war, the most exaggerated and commonly used method of inferior capacitors is to use low-voltage capacitors to pretend to be high-voltage capacitors. Some film capacitors with a withstand voltage of 630V are actually rated at 400V. After the voltage is false, customers feel that The price is obviously much cheaper. In fact, there is a great safety risk when the capacitor is used, and it will also cause the life of the capacitor to be significantly shortened.