What is the use of the black rubber ring for the high-voltage cable - Newheek X ray Cable

What is the use of the black rubber ring for the high-voltage cable

Some customers who have bought our high-voltage cables came to us and asked us what the black rubber ring on our high-voltage cables is used for. In fact, it is to prevent the high-voltage cables from sparking and arcing, but it may also cause the cable to not be inserted in the end. Poor contact. In addition, our high-voltage cables have protective sleeves to protect the high-voltage cables from breaking.
The plug of our high voltage cable is made of epoxy resin encapsulation process. If you want to buy our high-voltage cables, please come to know the situation.

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