Threaded: M5 / M6 / M8 /M10 / M12. one side is internal thread,the other side is rubber. Material: natural rubber and steel. Rubber Sizes（Dia x Height）: 15x15mm 20x15mm 20x20mm 25x25mm 30x20mm 30x30mm 40x30mm 40x40mm 40x30mm 40x40mm 50x30mm 50x40mm 75x25mm 75x40mm 75x50mm 80x60mm.
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