How can you knock one or two stars off a product due to your lack of knowledge or expertise? If you don't know how assemble or disassemble any part of a firearm properly, it should be done by a qualified gunsmith, especially the trigger group. Improper assembly of any firearm can be deadly dangerous. The install of these pins are easy with a few basic tools and a basic understanding of how your trigger system functions. I install these pins on every AR type rifle I own. They look great and prevent your pins from walking out (which I have witnessed at the range). I always encourage anyone who wants to buy an Ar15 learn to how brilliant the Stoner rifle design is and learn to disassemble/reassemble your rifle. You can always watch a YouTube video to show you how to swap any part on your AR. Remember, safety is number one.

This was so very easy to install. Go on "You Tube" and you will find the manufacture showing how easy it is to install. It is so easy a 6th grader can do it. Takes less then 5 minutes to install. You be glad you did.

Pro:
I like the KNS pin sets simply because they do stop wear on the pin holes which to me is worthwhile even if it normally takes a lot rounds to cause significant wear.
Also no wear should help keep trigger feel more consistent over time.

Con:
It is not normal for pins to walk out unless there is something out of spec or improperly assembled.
If a person is using these pins to prevent walking and they lose a screw then there is no hammer spring groove in the trigger pin to prevent walking.

Since I mostly run Geissele trigger groups I am waiting for the Geissele compatible kits.

These anti walk pins are top quality and do as advertised. Careful with the video provided. It shows the pins being installed incorrectly and reversed. Shows hammer pin in trigger and trigger pin in hammer. Per KNS, end notched pin with center groove goes in hammer as the hammer has the J-spring that fits in that groove. Also the trigger pin has oil reserve holes in it to keep a supply of oil at the ready for trigger rotation since the pins will now not rotate. Also don't use a hammer to install as shown in video. I have seen pin holes damaged by this technique and seen cast receivers chipped out around holes. Hand pressure is plenty and all the maker recommends. Watch their video. Other than that, every AR15 should have these installed. If your on a hog, deer or other hunt or LEO using this rifle, these pin locks could save your bacon. I've seen pins walk out under normal fire. I've seen hammer and trigger pins that don't fit well wear out the holes and cause issues such as engagement slippage which could let your rifle fire without notice. These pin locks stop all that and won't allow the pins to ever eat up the lower receiver holes. It's a little bit of insurance to keep your hunt on track or keep your rifle running if needed for defense. Lose a pin in the woods and most likely your hunt will be over. Lose a pin in a defensive situation and your life could be over. Doesn't seem like much but could be the best thing on your AR rifle. Best application is with 9mm, 45acp and select fire firearms as they produce much more vibrations to shake those pins loose and wear out the pin holes. Highly recommended. Might save you a trip to the smith.

I bought this kit for my Rock River AR after seeing it on multiple ARs in various magazines and websites and after reading the reviews here on Brownell's.

I guess I'll list the pros first. This kit looks awesome on your AR. I haven't owned any ARs for long enough to see the long-term benefits of having your pins stay in place so I can't comment on the effectiveness of the kit but it's easy to see how it would work. The including conical threaded punch is very easy to use, and the kit is indeed (mostly) drop-in as advertised. It takes all of 2 minutes to throw this in your gun.

Now the cons. The problem I have with this kit is that the hammer pin doesn't have channels cut in it to retain the springs. The trigger pin has a channel in the center, but not on the sides and the hammer pin is entirely smooth. The stock pins have these channels. With the KNS pins in my AR, I believe the lack of spring cuts in the pins caused binding which prevented the hammer from dropping. When dry-firing I had to put sideways pressure on the trigger to get it to drop. Live fire was the same, but double taps or quick firing made it slightly easier. That being said, I'm not a gunsmith so it's possible that these issues are easily resolved using a sneaky trick or two.

I docked the KNS pin kit 2 stars because it as advertised as "drop-in," yet seems to require machining to function properly, and the malfunctions this causes could endanger the weapon operator in dangerous situations. I wish this product performed better, but I refuse to have a part in my gun that's so important to the function of the weapon that causes it to not fire or a delay in firing. I took it out of my AR pending a consultation with the gunsmith.

These things are fantastic. First introduced to me at an aromorer school I got some and put them on my rifle. Really easy install, they look good on the rifle, and the smoothed out my trigger pull. KNS knocked it out of the park with these.

This is a rather nice kit. I installed it on a rock river arms rifle to prevent any problems and on a dpms to keep a problem from getting worse. Both worked great. Easy install. The instructions dont explain it well but the little brass cone in the kit will thread into the trigger pin and you can use it to push the old pin out. works like a charm. looks neat and clean as well

The next test is live fire at the range. IF that works, the 5 star rating is accurate.
Note: Brownells video on the KNS pin set has the hammer and trigger pins reversed! AR15 hammers have a centering spring, therefore, the hex screws go into the trigger pin, not the hammer pin.

Truly a 60 second install and looks great on my LOKI lower. By the way... as stated in another review , I can feel a slight improvement in the trigger pull. The reason for the 4 stars is that one of pin keepers was slightly bent but easily straightend.

I installed these pins on my Smith & Wesson M&P15, they were very easy to install, and smoothed out my trigger a little. They look great on the weapon, and function exactly as advertised. They have withstood over 3,000 rounds of both full auto and semi auto fire, and still work perfectly.

Easy to install. It comes with everything you need. Just read directions first. Looks good and fixes the problem it was designed to correct. Have installed these on my Armalite AR-10 A4 as well.

These pins installed in my S&W M&P-15 in seconds, litterally. No Muss No Fuss, I took them to the range the very next day and maybe its just me but my trigger broke cleaner than I remember. Plus they look great, shows that you care about your rifle.

Good protection for your lower receiver. Very easy to install, and I like the smaller, lower profile. Good price too.

These are great for Ar'S that the reciever holes for trigger& hammer are worn. Make sure you get reamer. If you
shoot match it makes a differance.

Does exactly what it is supposed to do with extremely easy installation. Literally about the easiest item I've ever installed on an AR. Parts are machined from top quality materials.

Bought two sets for Colt AR 9m/m. Easy to install, drove in new pins without disassembly****on installation, discovered old hammer pin on one carbine broken in half at center******

These Pins look great and went in easily. On my particular gun they seemed to increase the trigger pull but made it more crisp. The Gen 2 Mod 2's are the most discrete model and they are as strong as the thicker models. Great for 9mm and 22 blow back operated AR15 variants.

Used this on my SBR lower. I was iffy at first about doing this cause I was afraid it may damage the Cerakote I had the lower coated in. But it went on fine just knocking out the old pins with the new ones you dont even have to dissasemble anything and nothing got scratched. Very rugged and works as advertised. Hey our lowers are expensive enough especially SBr ones so why not make sure they last? By the way these arent allowe don certain match guns.

These pins replace your factory hammer and trigger pins and prevent them from walking out of the lower receiver. They are durable and fairly easy to install, but still require some knowledge of how to install the trigger assembly since it is likely that some of the small trigger parts may move and will have to be reset properly (hence the 4, not 5 star rating). The easiest way to install these pins is to try to use the KNS pins as slave pins and push the factory pins out using the new KNS pins.

I could not belive how easy they made it to install. Looks great.