Redline N7 Gen-2 Milsim Mechanical-Pneumatic HPA Conversion Kit (Version: Version: Ver. 3 / AK)

"Put this in a matrix calico jack only thing I had to do was dremel out 2 support beams then it fit perfectly. This engine works amazing it doesn't use a lot of air, not having a battery is amazing, it shoots awesome and it's overall such a good engine for the cheap price (for a hpa engine)

"Re-reviewing this because I did a second build with the gen 2 version. Reiterating my previous review, the gen 2 also works without the trigger spring. You will need to use an AEG type trigger, HPA type speed triggers will not work as there is no microswitch. Another review also mentioned that Krytac gearbox shells require modification, I would extend that to most ambidextrous gearboxes. This is because the pin that goes through the value assembly line ups with the bearing hole just behind the trigger. For Krytacs ( and other ambi shells) this hole is larger because of the selector switch assembly parts for the right side fire selector functionality. The trigger value in the gen 2 is significantly bigger than the gen 1 so I did end up removing the cutoff lever to get it to fit. Definitely would recommend this over the Kythera if you are looking for a mechanical pneumatic HPA drop in. Hope this helps somebody!

"I have used the gen 1 version of this in my primary for over 5 years now with no issues. I run this with a prowin hopup chamber, and a modify hard type baton ryusoku bucking with 0.3 gram bbs. Outperforms my upgraded TM VSR-10 in terms of range. This has worked with every gearbox I own: G&G, APEX, CYMA, and WE tech. Great performance. The field I play at is semi only so I have no issue with using a mechanical system. Really solid performance and the bare minimum maintenance required. Gas usage isn't terrible and I have not had any major issues. I did have a busted o-ring but redline sells a replacement kit for fairly cheap on their website for both the gen1 and gen2. I am very pleased with this purchase. The grip line on this is a bit flimsy but not really an immediate issue and amped has grip lines compatible with the n7. Also nice that it has a metal nozzle that has held up to the regular wear and tear for 5+ years. One thing to note is that speed triggers don't work too well in this. However, you do not need to use a trigger spring as the valve spring has enough tension so you can still have a very light trigger pull with this (at least for the gen1, I cannot say for certain about the newer valve). Just make sure if you do change the trigger to get an AEG type meaning it has to have the elongated back part in order to engage the valve properly.

"nothing i can complain about, I own the Ak model. performance is great but it does get a little boring after a while, being stuck with semi

"WOW!!!

Installed 3 of these so far, all have performed flawlessly.
The first went into a VFC Colt Licensed Tan MK18 MOD1 Full Metal VR16 and the only issue was that the unit came with the micro hoses reversed from Redline, and they responded immediately to my email, so it was a very simple fix.
The 2nd went into a G&G CM16 Combat Machine, super easy and fast, turned that lightweight gun into a lazer.
The 3rd was a lot of work. I went all out and put it into a Krytac Trdent MKII SPR, which is not recommended by Redline. But I had already gutted the gearbox, so after lots of grinding I got the trigger unit to fit and now have the gun I wanted. I can't wait to see how she performs.

Best of all, NO BATTERIES

"This was the first HPA kit I've ever used, and I absolutely love it! Went in with no issue at all and works like a charm! The instructions that come with it have pictures to help guide you for correct placement. Totally recommend!

"Consistency is king. It'll hold up and function as normal in rain, sleet, and snow. It fires as fast as you can pull the trigger as long as your regulator works right. I've gone up to 120psi and gotten 480fps with .2g bbs to stress test it. Redline sells nozzle drop ins that are super easy to install and as long as the gearbox is v2 the nozzle exists you can get it to work. Example: My ICS Transform 4's nozzle is an AK nozzle so when I had the M4 nozzle that came stock, the consistency was all over the place. If you're not rocking a TM standard m4 then do research on your nozzle type for perfect fit. Ran this engine for 4 years and ran it through the ringer. Still working how it did when I got it.

"These are simple and awesome HPA engines. RedLine's customer service is one of the best I have ever seen in my 9 years of playing. Very easy to tune and install with a very clear color included instructions. I only wish that they were more in stock so I can buy a couple more.

"I love this HPA!! This was my very first time buying a HPA System. I paired it with the Redline V2 HPA stock for my A&K SR-25 and it dropped in with ease. There has been no problems with it after 2 years, with constant weekend airsoft runs. I put a mock silencer on it ( with foam cut outs) and you can barely hear it.

"This is an amazing system, built reliably, strong, and shoots so far. You can dunk this thing under water and still have to work. Makes playing in the rain look easy. I've gotten a lot of compliments because of this system and extremely happy with it. I run a Valken Alloy Series Mk2 with an Angle Custom drum mag, as well as a Amped Airsoft tank, line, and regulator.

"Put this into a m4/spr build with a G&P donar m4. I'm running a Wraith stock with it. This is my first HPA build. I am really enjoying it. The gun shoots flat and consistently. With the co2 stock, I only see the FPS drop when the co2 is about to run out.

"Question: I heard that these are compatible with the wolverine wraith stocks. Is this true?

"came without any oil/grease in the trigger valve, wouldn't work right until I took it apart and got some grease in there. be warned, you may have to oil the thing before using it. a blast of silicone oil in the trigger valve should do it, but I didn't have any with me on the field.

works perfectly after lubing everything up, it's fun to use and very consistent. very quiet shot with a very poppy reset, very tactile and satisfying trigger pull. it's just super fun to use, and no one can complain about getting too overshot or auto'd. fire rate is about as quick as you can pull it, I'd recommend an adjustable trigger with post travel adjustment, as pre travel can be adjusted through the valve itself.