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Condolences to epidemic prevention workers

In recent years, the national epidemic situation has been repeated. In order to respond to the government's call to ensure the import of external prevention and the repeated internal prevention, various departments of Luotang Street, Jiangyan District have joined the anti epidemic army. The epid

social responsibility

When it comes to power cables, I believe everyone is familiar with them. We can often see and use them in our daily life. If we look closely, we will find that these power cables are wrapped by insulation. What do you know about the insulation of wires and cables? What types of insulation materials