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ProMag AR-15 Flip Up Front Gas Block Sight Adjustable for Elevation Quick Detach Aluminum

Pro Mag
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ProMag AR-15 Flip Up Front Gas Block Sight Adjustable for Elevation Quick Detach Aluminum

The PM138 front sight body and stem are machined from T6 aircraft grade aluminum and type III hard anodized. Steel parts are machined, then black phosphated per mil-spec. Precision machined to fit dovetailed gas blocks meeting MIL-STD 1913 Picatinny rail specifications. The sight is mounted to the gas block via a locking bar and secured with a cross slotted, knurled thumb screw.

The sight is adjustable for elevation, (a quarter turn) moving the point of impact 1.25 MOA (minute of angle) at 100 yards. The front sight features straight protective ears. The sights stem folds up and towards the shooter to deploy. When in the up position the sight is locked in place via a spring loaded plunger. To fold the sight to the down position, depress the plunger and fold the sight stem forward. No permanent modification required for installation. All hardware included. The PM138 sight may be paired with model PM136, PM137, PM200 PM202 rear sights mounted to AR-15 / M16 flat top A3 upper receiver rifles and carbines. 

Item#: ARR-163,3-1022455,6-1022455,2-PM138,82741
Total number of Reviews: 10

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5.0 5
"Bought with the rail gasblock, lines up correctly height wise with ARMS rear sights. Good value considering cost."
– WK
3.0 5
"The sight, itself, is solid, however the picatinny mount is off-spec (measuring 0.895\" instead of 0.835\") so it cannot be properly secured without shims. I do not know if this is a systemic problem with ProMag or if this was just a bad unit."
– DD
4.0 5
"This is a very good product. I used this and the promag rear sight on a SNS M4, that I also added a aimpoint compM4 to. Had it out this weekend, no problems, with zeroing or holding zero. Im adding another two to my \"shopping cart\" as I type this. Oh.. same as the GGG front sight."
– Mr. D.
5.0 5
"I put this sight on a freefloat forearm to see if it would line up with my A1 upper rear sight. Looks to be good with minimal adjustments. Sight functions well and mine attaches well to rail on forearm. A good valuein my opinion."
4.0 5
"The front sights are better than the rear ones you can order. Mine did not fold up all the way but I removed the 2 allen screws and then backed off the allen screws under those and it evened out. Quality is good for the cost."
– chad
2.0 5
"So I bought the matching set and mounted them on a RobArms XCR, they went on smooth and tight. When I went to sight them in I had a problem. My grouping were way low by about a foot. I aimed at the head and hit the chest. Not good. That's where things get tricky, see the front sight post was already as low as it could go on adjustment, meaning that was as high as I could get my grouping without modification to the post itself. I had to file the post a little at a time as was able to bring the grouping up only about 3 inches. As of now it's still aim high...very high."
– FreedomFighter
1.0 5
"This front sight had a really wide post. I went to change it with a KNS precision sight, but the front sight tool would not work because the ProMag post was so poorly made. Even the 3 prong tool in my Samson Field Survivor wouldn't work. Once I got the post out, I found is was nearly 1/8\" shorter than a mil-spec front sight post above the threads. The threads were so rough, the mil-spec sight would not thread in anyhow."
– mike
2.0 5
"This sight does work in theory, but if you don't use a torque driver or something to keep from getting it too tight, it strips the clamp screw out of the aluminum nut recessed in the side. It also seems to lean a little off center when properly tightened."
– IronWulfenn
1.0 5
"Was not a well manufactured item removing and installing a time or two and the aluminum clamp nut is stripped rendering it useless. It leans to the side a little even with proper torque."
– Ironwulfenn420
4.0 5
"Pro Mag gets it done at a much better price. I have both front and back on my Armalite and they hold in place after thousands of rounds."
– 19k