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Luth-AR A1 Rear Sight Assembly UR-21A Condition: New, Color: Black, Finish: Anodized,

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Luth-AR Rear Base Sight Assy A1 UR-21A
Luth-AR Rear Base Sight Assy A1 UR-21A
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Luth-AR Rear Base Sight Assy A1 UR-21A

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Questions & Answers
Customer Reviews
Helpful Positive Review Bought for several builds, never had an issue by M, Verified Owner, July 12, 2023
Honestly, it's exactly what it is. An A1 rear sight. It's a pain to install, pain to adjust, etc. Before you start your build make sure you use copious amounts of gun oil on the upper, this will help you greatly with the install. To be clear, this is...
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1/1 found this helpful
Helpful Negative Review Out of spec parts by TK210, Verified Owner, November 3, 2020
I have a Luth AR A1 upper and these parts are out of wildly out of spec. The leaf spring is too tight and therefore I can't turn the windage drum once installed. The leaf spring is so tight that the rear sight doesn't even flip down all the way. S...
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1/5 found this helpful
Most Recent Reviews Windage Drum Sucks by Your Mom Says Hi, March 5, 2025
Luth, I usually dig their stuff, but the hole in the windage drum was waaaaaaaaaaay to small for the supplied roll pin. I should have known better. There are numerous others with the same issue. Nothing I could do short of opening up a bit, and I ...
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Most Recent Reviews A1 REAR SIGHT by William Tinsley, Verified Owner, July 21, 2024
Great for finishing my a1 copy build. Authentic style rear sight.
Most Recent Reviews LUTH-AR A1 REAR SIGHT ASSEMBLY by William Tinsley, Verified Owner, July 14, 2024
Works great easy to install just what I needed to finish my a1 build.
Most Recent Reviews Leaf spring too large/stiff by Matt B, September 22, 2021
Leaf spring is too long and stiff to fit in the Luth Ar upper. Barely able to install the sight and windage adjustment is impossible to use due to the excess tension. Now I have to disassemble the sight and find a new leaf spring.
1/3 found this helpful
Read All 10 Reviews
Condition: New

Code: 3FN-ARI-164LUTH-UR-21A

MPN: UR-21A

UPC: 859992007135

$27.99

Product Info for Luth-AR A1 Rear Sight Assembly

Whether you're doing a new build, rebuild, or just replacing your A1 Rear Sight Assembly, these AR 15 Parts from Luth-AR is the complete package. Designed for an A1 upper receiver, it's combined with the front sight (not included) to give your retro Mil-Spec AR the look and performance of the iconic rifle.image

Specifications for Luth-AR A1 Rear Sight Assembly:

Manufacturer: Luth-AR
Condition: New
Finish: Anodized
Color: Black

Features of Luth-AR A1 Rear Sight Assembly:

  • All-steel construction
  • Non-reflective matte black finish
  • Complete rear sight assembly kit

Package Contents:

  • Luth-AR A1 Rear Sight Assembly

Luth-AR A1 Rear Sight Assembly Orderable Models

List of Orderable Models

Luth-AR Rear Base Sight Assy A1, UR-21A , MPN: UR-21A , UPC: 859992007135 , Code: 3FN-ARI-164LUTH-UR-21A
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