"I bought this for my kwa km4a1, and found out that kwa does not have a mil-spec upper receiver thread pattern. So the barrel nut that came with this rail system would not screw all the way on. So I bought a re-threading die for ar-15s and re-threaded my upper receiver. Its a great rail system that is very light weight. I would buy this again!
"Great product with a solid feel and very good finishing all around. Easy installation onto an APS Upper Receiver, with just the tiniest amount of tinkering to get the barrel nut to line up properly. Be careful, if you wind the nut too tightly it may lock up on the upper receiver and you will go red in the face trying to get it re-positioned!
Just as a side note, in the pictures it shows 4 bolts that secure the hand guard to the barrel nut, two on the left, two on the right.
The version that shipped to me only had two bolts that screwed in from the bottom to hold the guard onto the barrel nut. It still secured the guard tightly with no wobble whatsoever as the profile wraps onto the receiver, but I wold have liked more for peace of mind.
Also, the picatinny rail was just a millimeter higher than the receiver rail, so there is a noticeable step, but has not affected the mounting of any of my scopes.
Otherwise feels great on the rifle, much like a G&G Predator and nice comfortable grip. The rest has been covered in the other review before mine.
"This is most likely the cheapest, and best quality KeyMod rail system money can buy. I had a bit of difficulty installing it on my Tippmann M4, and realized the dust cover pin was impeding the rail, so I had to file some off the pin, and it works beautifully now. The design is very sleek, and relatively light so your M4 isn't too front heavy. There are 2 QD sling swivel mount points, in case you feel like running a 2 or 3 point sling. Out of the box it comes with the barrel nut, mounting screws, and three 9 slot KeyMod rail sections. (Real spec KeyMod compatible) The rail sections are die cast metal, and are solid, but heavy. A nice installation guide in English was also included in the package. I'm not entirely sure why they made it, but there is a barrel stabilizer that screws into the front end of the rail system, and goes around your outer barrel. The finish has a very nice anodized feel, and isn't going to change anytime soon. "Boar Tactical" and "Low Profile Adapt Rail System" are laser etched on the side, and marked rail sections and other marking adorn the top rail. Bottom line: if you're looking for a nice KeyMod rail and don't want to shell out big bucks, this is for you.
Pros: affordable, well made, durable, lightweight, comfortable, comes with keymod sections, real spec
Cons: annoying install, heavy keymod sections