First off let me tell you a little about me

I have owned and run my own store for over 7 years, We are Smartparts Certified Techs, I am also a toolmaker / machine builder for over 22 years

There our people on ebay selling QEV kits with teflon tape installed on the threads this a big no no, Teflon tape is used to seal NPT threads (taper threads) The teflon tape on a straight thread doe's nothing but come off and screw up your marker. 

95% of the time when a QEV install leaks it is because of the position of the hoses and not the QEV.

For Quailty instuctions and information buy, from someone who knows what they are talking about !!!  

The main reason for a QEV upgrade is to change the way the marker fires, by adding a QEV you redirect the gas (CO2 or Compressed air) from the solenoid to dump out the QEV (Quick Exhaust Valve) which in turn lets the marker respond fasted which in turn allows you to lower the dwell . This gives you better Air Efficiency. This is by far the best  upgrade that you can do to your ION.

QEV's can also be used on autococker Rams! 

Millennium-Paintball