+1-800-504-5897 Help Center Check Order Status
About Us Policies Reviews How To
Free Shipping & Free Returns*

FREE SHIPPING on Over 250,000 Products

Shop now and get Free Value Shipping on most orders over $49 to the contiguous 48 states, DC, and to all U.S. Military APO/FPO/DPO addresses.

Enjoy our FREE RETURNS

We want to ensure that making a return is as easy and hassle-free as possible! If for any reason you are not satisfied with your purchase, simply return the item within 30 days of receipt, and we'll cover the cost of return shipping. Learn more about our Return Policy.

  • Entire Store
  • ...
  • Apparel & Footwear
  • Astronomy
  • Everything Else
  • Eyewear
  • Hunting Gear
  • Lab Equipment
  • Military Gear
  • Outdoor Gear
  • Photography Equipment
  • Police, EMS & Fire
  • Shooting
  • Sport Optics
  • Sports & Hobbies
TIP
Shopping Cart

Luth-AR A2 Rear Sight Kit UR-21K Gun Make: AR Platform, Gun Model: AR-15, $4.80 Off w/ Free S&H

Special offer available for this product. Click here to see!
Limited Time Offer. Click here to see!
Luth-AR A2 Rear Sight Kit, Black, UR-21K
Luth-AR A2 Rear Sight Kit, Black, UR-21K
Luth-AR A2 Rear Sight Kit, Black, UR-21K
1 of 2 images
Luth-AR A2 Rear Sight Kit, Black, UR-21K
Luth-AR A2 Rear Sight Kit, Black, UR-21K
2 of 2 images
Luth-AR A2 Rear Sight Kit, Black, UR-21K

Tap Tap to Zoom

Questions & Answers
where is it made Manufacturer Answer

like all Luth-AR products the A2 rear sight kit is made in the USA.

by Luth-AR, Manufacturer, November 27, 2024
View All Q&A You Have a Question? Ask!
Customer Reviews
Most Recent Reviews
a usable rear A2 sight at a decent price by Leon, Verified Owner, November 12, 2025
This sight comes completely disassembled, so one should be careful, especially with the detent balls, as they can be easily lost (using grease helps to keep them in place). This rear sight is not as tight to the receiver as the one from RRA, but it i...
Read More...
Most Recent Reviews
Solid build and finish. by Ralph, Verified Owner, September 1, 2025
Quality components and matched with the Luth A2 upper perfectly. Little play and hold zero. Positive elevation settings.
Most Recent Reviews
Luth-AR A2 Rear Sight Kit by Owen, Verified Owner, March 22, 2025
I used this to complete a stripped A2 fixed carry handle that I had laying around. Luth-AR makes good products, this one included. Just be careful not to drop the tiny ball bearings while assembling, since it only came exactly three pieces w/ no extr...
Read More...
Most Recent Reviews
Haven’t been to the range but it assembled just fine by Lo, Verified Owner, December 11, 2024
No parts were missing, dials feel tight but not hard to rotate, color seems to be a shade off from the upper(darker). Can’t complain but haven’t been able to test it yet
Most Recent Reviews
Luth ar a2 sight by Austin Turner, Verified Owner, November 17, 2024
Works awesome on my rifle would recommend on any retro build
Most Recent Reviews
A-Ok, completely unassembled though by HCM, Verified Owner, November 6, 2024
Good sight, good finish with quality components. Had no trouble with it. I feel like some of it should have came assembled (aperture and windage knob), and wouldn't have hurt to thrown in an extra spring and bearing because they'll get lost on you in...
Read More...
Read All 7 Reviews
Gun Make:
AR Platform
Gun Model:
AR-15
Sight Position:
Rear
Front Sight Color:
REAR SIGHT ONLY
Rear Sight Color:
Black

Code: 3FN-ARI-LU0429-UR-21K

MPN: UR-21K

UPC: 812058031383

List: $79.95Save $4.80
$75.15

made-in-usa-flag Made in USA

Help support American manufacturing! Marked models of this product have gone through rigorous review and been certified by the manufacturer as Made in the USA.

Product Info for Luth-AR A2 Rear Sight Kit

A2 Rear Sight Assembly/Kit is for Mil-Spec A2 upper receiver.image

Complete A2 rear sight kit. This kit requires assembly and will mount on an A2 upper receiver.

Specifications for Luth-AR A2 Rear Sight Kit:

Manufacturer: Luth-AR
Gun Make: AR Platform
Gun Model: AR-15
Sight Position: Rear
Front Sight Color: REAR SIGHT ONLY
Rear Sight Color: Black
Country of Origin: USA
Gun Type: Rifle
Color: Black

Package Contents:

  • Luth-AR A2 Rear Sight Kit
  • A2 Rear Base Lug
  • A2 Rear Sight Aperture
  • Rear Base Flat Spring
  • Rear Base Windage Knob Screw
  • Rear Base Windage Knob
  • Rear Base Spring Pin
  • Rear Base Spring
  • Rear BaseBall Bearing
  • Rear Base Index Elevation (8/3)
  • Rear Base Elevation Knob
  • Rear Base Elevation Knob Spring
  • Rear Base Spring Pin
  • Rear Base Index Screw

What firearm models does the manufacturer say Luth-AR A2 Rear Sight Kit is compatible with?

The manufacturer says that Luth-AR A2 Rear Sight Kit is compatible with AR-15

Luth-AR A2 Rear Sight Kit Orderable Models

List of Orderable Models

  • Luth-AR A2 Rear Sight Kit, Black, UR-21K , MPN: UR-21K , UPC: 812058031383 , Code: 3FN-ARI-LU0429-UR-21K
Compare (0)
1 item has been added
Add at least two items to compare