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TWS English: True Wireless Stereo, which means true wireless stereo. The realization of this technology is based on the development of chip technology, which means that the mobile phone is connected to the main speaker through the main speaker, and then the main speaker is connected to the slave speaker through Bluetooth wireless mode to realize the true Bluetooth wireless separation of the left and right channels. When the slave speakers are not connected, the master speakers return to mono sound quality. TWS technology uses the field of Bluetooth headsets, so it also spawned a new product-TWS Bluetooth headsets.

Battery transportation and circulation in the market of each country must be tested and certified according to the corresponding certification standards. The general battery certification is divided into the following types according to different national standards:

If you have a certification plan for exporting batteries to South Korea, please pay attention to the early change of KC certification standards to avoid export troubles.

There is no standard for \"standardizing\" or improving the implementation of the civil protective mask market. According to the standard, the mask protection level is divided into four levels from low to high: D, C, B, A, respectively corresponding to different air quality conditions.

The outbreak of new coronary pneumonia led to a surge in demand for masks. At present, the domestic epidemic situation is tending to ease, the number of infected people in Europe, Italy, Japan, South Korea and other countries continues to rise, and Iran has attracted global attention with a very high lethal rate. In view of this, the business opportunities of masks quickly moved abroad, and the export of masks has become a hot business in the epidemic.

Since the lithium-ion battery interview, after just four years, he has faced his first crisis: more than 1 million lithium-ion batteries in the Sony County Hill factory caught fire for unknown reasons. Subsequently, it took Sony five months to persuade the Tokyo Fire Department to avoid the \"dangerous goods\" label on lithium-ion batteries. At the same time, Sony has also conducted a lot of research on the safety performance of lithium-ion batteries, and the safety test standards for lithium-ion batteries have begun to gradually improve.

Since the lithium-ion battery interview, after just four years, he has faced his first crisis: more than 1 million lithium-ion batteries in the Sony County Hill factory caught fire for unknown reasons. Subsequently, it took Sony five months to persuade the Tokyo Fire Department to avoid the \"dangerous goods\" label on lithium-ion batteries. At the same time, Sony has also conducted a lot of research on the safety performance of lithium-ion batteries, and the safety test standards for lithium-ion batteries have begun to gradually improve.

Recently, the European Safety Federation (European Safety Federation) published an article on its official website to \"fake\" the current CE certificates of some personal protective equipment (PPE). It also said that protective masks (FFP2 or FFP3 type), protective glasses and Personal protective equipment (PPE) such as face masks, protective gloves, and protective clothing must meet the REACH regulations in addition to the currently focused CE certification.