Thick: 1mm 1.5mm 2mm 3mm 4mm 5mm. ID: 1.5mm 2mm 2.5mm 3mmm 3.5mm 4mm 5mm 6mm 8mm 10mm 11mm 12mm. OD: 4mm 5mm 6mm 7mm 8mm 9mm 10mm 11mm 12mm 14mm 16mm 17mm 18mm 19mm 20mm 21mm. Feature: waterproof, oil-proof,shock-absorbing, and good sealing.
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