Barter is the present and the future of international trade, especially for people who is starting in the import export business. Barter and more: Triangular operations.
The advantages and disadvantages of LED traffic lights
1. Look at its material. That is to say, look at its surface, whether it is high-grade or low-grade; what brand and chip of the LED are, and whether it is bright enough; what circuit is used for the power supply, and what brand or cottage factory is the electronic device in it.
2. Performance test. Test its sensitivity, anti-interference ability, time accuracy, and the accumulated time error is not large.
3. Safety test. There are many test items, more frequent switching, high pressure and so on.
