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SIG SAUER Factory Replacement M-LOK Sight Rail for M400 TREAD
$46.99 $37.49
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Most Helpful Positive Review Only from Sig
Fits the tread and it’s the only one guaranteed to fit the sig tread. It goes on simple and is very secure. Price and shipping were not bad. However, I would suggest getting the sig tread sights as they come with this rail. That is all you need
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Perfect LOW PROFILE Picatinny Rail Section

by Dave, Verified Owner from MA, United States Written on July 20, 2025
Mounted this on the front of Ruger PC Carbine 9mm rifle handguard that had no front sight post. A standard Picatinny rail to mount was too high to prohibiting the installation of a flip up iron sight since it was then higher than the receiver's rail. The lower profile of this piece enable the installation of Meprolite's Trid front flip up post. It's well made and worked perfectly.
Pros:
  • Low profile
  • Construction
  • MATERAIL
Cons:
  • None
Best Used for:
  • M-LOK RAIL
Would recommend: Yes
Was it helpful to you? Yes | No

Needed to add front sight on Sig M400

by Joe, Verified Owner from NC, United States Written on December 24, 2024
Wish this was included with the rifle as this is needed to add front back up sights on the Sig M400 if you are also running an optic. Well made and easy Mlok installation.
Would recommend: Yes
Was it helpful to you? Yes | No

M400 front sight rail.

by Xamyert, Verified Owner from OK, United States Written on February 20, 2024
The item was perfect. But for some reason they decided to use DHL to ship. It took forever! I don't understand why they would to that.
Would recommend: Yes
Was it helpful to you? Yes | No

Sig m400 spacer plate

by Gnu, from FL, United States Written on February 19, 2024
After searching numerous web sites with intent of purchasing the Sig Sauer spacer(picatinny)rail for the front iron sight of my new Sig M400 Tread I was happy to find it at a great price at Optics Planet.
Would recommend: Yes
Was it helpful to you? Yes | No

Front sight pic rail

by B Hife, from IA, United States Written on February 14, 2024
Super east install and over priced, but have to have it if you want to run irons ��‍♂️
Would recommend: Yes
Was it helpful to you? Yes | No

Great product

by Shorty, Verified Owner from CA, United States Written on December 22, 2023
Easy to install and fit perfect on my Sig M400 handguard.
Would recommend: Yes
Was it helpful to you? Yes | No

Mlok front sight rail.

by Sig fan 123, from MS, United States Written on September 19, 2022
Works great. Works exactly how it ought to. Like it should. Like sig would. Like they should. I love the sig m400. Nice Molly rail sight attachment. It’s the perfect height to line up your back sight to get accurate shots at the range.
Would recommend: Yes
Was it helpful to you? Yes | No

Lower Profile Mlok rail, Works on my Lancer Handguard

by DanJM, Verified Owner from MI, United States Written on March 24, 2022
I was on the lookout for a slightly lower profile rail section so I could add a rail on the top section of my Lancer Carbon Fiber handguard. It's been shockingly hard to find a rail that will mount at the same height as the receiver rail.
This one does. It may be made for the Sig TREAD, but it also seems to be the right height for other rail systems lacking a built in rail section. As long as you have an MLOK slot, it should give you the option for a sight rail.
Pros:
  • EASY INSTALL
  • Quality build
  • low height
Cons:
  • None
Best Used for:
  • hunting
  • Target shooting
  • Tactical
Would recommend: Yes
Was it helpful to you? Yes | No

Sig Sauer Factory M-LOK rail for M400 Tread

by Justin Pickering, from IL, United States Written on April 14, 2021
Good for mounting a front back up iron sight on the Sig M400 Tread rifle or pistol because it matches the height of the upper receiver on the Sig M400 Tread it's a metal rail segment it's pretty durable only con is the price
Pros:
  • Matches height of Sig M400 Tread upper receiver
Cons:
  • price
Best Used for:
  • Mounting a back up front iron sight
Would recommend: Yes
Was it helpful to you? Yes | No

Perfect for tread

by Joel M., from TX, United States Written on March 26, 2021
Obviously this sight rail is made by sig for the tread so it’s perfect for the tread. I have basic mbus sights as backups and this piece of rail is perfect for the front sight. The rail section is small and that’s obviously what’s intended it’s just long enough for a sight and it keeps the hand guard simple and clean.
Pros:
  • Small
  • Minimal
Cons:
  • None
Best Used for:
  • Mlok handguard
  • Sig tread
Would recommend: Yes
1 of 1 found the following review helpful.
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