Connecting two ends of pneumatic tubing?

[FrankJ]

Keep in mind pneumatic tube comes in a wide variety of plastics. Some would be useful in this application, some not so much. Better to use polycord as others have said.

[pipsqueaker]

Use polycord, pneumatic tubing isn't nearly as flexible as an intake would require it to be

The plugs are good, but in my experience with polycord they're not immune to failing.

Some plastic-metal superglue will do the trick though. I like to use a bit to bond the plug to the tube, mate the two ends, and then glue those mated ends together as well