M3 OD 5/6mm Aluminum Alloy Standoff Spacers Round Threaded Sleeve Nuts Connector. Thread Size:M3. Spacer Length: 6mm，8mm，10mm，12mm, 15mm, 18 mm，19mm，20mm，21mm， 22mm， 25mm，26mm，27mm，28mm. Can be used as connecting rod, fixing rod or supporting column.
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