The Forge Motorsport 004 Blow Off Valve is a dual piston design. This allows the port on the charge pipe to be closed during idle. This unit can be used with a MAF. Downside is you will run slightly rich during shifts. But the ECU adapts so quick, it does not make it a big issue. I have also taken this unit apart and serviced it. This will come with the green spring, and is to be used for boosting up to 15psi. You will need to purchase the tuning spring kit if you require a different spring. It is the same spring kit used with their diverter valves, such as the 006 and 007.
This item is used and it shows it. It has it's fair scratches, scuffs, and gashes. But does not deter from functionality. Take a good look at the pics, and pricing reflects from the cosmetic wear.
Price is $75 shipped in the continental US. If wanting to buy outside the 48 states, contact me for exact shipping quote. Any questions, feel free to ask (send me a PM, because it goes to my email. I hardly check here). Pick up available for lesser price. Not by much, but is still cheaper. I think prices are already fair to begin with. Thanks for looking!