Material : 65MN Manganese Steel. They are durability and beautiful and smooth appearance.360° inner ring precision design, good sealing, a good fixed hose and pipe body connection. You only need to press the clamp lug hard to make the inner ring larger, you can put it into the round tube, and then release it, you can clamp it, and it is more convenient to use with the clamp and can be used repeatedly.
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