How to buy RJ45 with transformer?

There are many network transformer suppliers in the market, but now with the expansion of the market, the demand is growing. How can I buy so many RJ45 transformers? In fact, there are many ways to buy. Alibaba or Baidu, for example, can find manufacturers to buy, you can also visit manufacturers or compare several, you will find how to choose. Using RJ45 belt transformer can enhance the signal and make the transmission distance longer, isolate the chip end from the outside world, greatly enhance the anti-interference ability, increase the protection to the chip (such as lightning strike) , secondly, when connecting different levels (if some PHY chips are 2.5 V, some PHY chips are 3.3 V) , the network port will not affect the other device. The RJ45 connection of network transformer is mainly used for signal level coupling. First, the signal can be amplified to make the transmission distance longer. Secondly, the chip can be isolated from the outside world, greatly improving the anti-interference performance. The chip also has a strong protective effect (such as simulated lightning strikes) . Connecting different levels of the network interface (if the PHY chip is 2.5 V, part of the PHY chip is 3.3 V) , will not affect the performance of the other device. Direct grounding is not usually used in distribution transformer operation, but it must be well grounded. The lightning rod can be installed between the high-voltage fuse and the transformer to ensure the neutral grounding effect and no spot phenomenon.