Description
The LRPK-BLDR Lower Receiver Parts Builder Kit from Luth-AR is ideal for anybody assembling an AR-15 who needs all the small bits-n-pieces to complete a stripped lower, but who wants to customize the performance-critical components. You supply the trigger/fire control components, pistol grip, buttstock/buffer system, and triggerguard of your choice. Luth-AR’s Builder Kit covers everything else. No need to purchase all these commodity parts separately, only to sit down on a weekend to do your project…and find out your missing one or more small bits! The complete contents of the LLRPK-BLDR lower receiver parts kit are:
- Buffer Retainer & Buffer Retainer Spring
- Safety selector lever + detent
- Selector/Ejector spring
- Bolt Catch + spring, plunger & roll pin
- Magazine catch
- Magazine release button (aluminum)
- Front pivot pin
- Rear takedown pin
- 2x Takedown/pivot pin detents
- 2x Detent springs
- 2x hammer/trigger pins
- Mag Catch/Buttstock Plunger Spring 1-ea.
All of these Luth-AR LRPK-BLDR Builder Kit parts are standard AR-15 parts designed to fit a “mil-spec” lower receiver. Almost all currently available lowers are dimensioned to accept these parts, so compatibility should not be a problem. If you’ve assembled an AR-15 before, you should have no trouble installing these components.


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