0-EFLH1158 E-flite O-Ring & Tubing Set: BCP, BCPP, B400 <p><font color="00ff66" size="2" face="Arial, Helvetica, sans-serif">Inner diameter: 3mm<br />

Outer diameter: 6mm<br />

Do not use a petroleum-based lubricant such as Vaseline. Instead use a silicone-based lubricant.

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