Anderson Manufacturing AR-15 Lower Parts Kit - Stainless Hammer and Trigger

Manufactured by Anderson Manufacturing
MPN: G2-K421-A000-0P
Manufactured by Anderson Manufacturing
93 Reviews

In Stock

Standard orders will ship out within 1 business day if ordered by 3:30 pm CST, Monday-Friday. FFL orders will ship within 5 business days or less as long as we have the information for the transfer destination.

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Anderson Manufacturing builds rifles, pistols, and parts utilizing the latest in computerized manufacturing. By keeping manufacturing in house, Anderson can offer quality, American-made products at an affordable price, backed by a limited lifetime warranty.

The Anderson Manufacturing Lower Parts Kit contains almost everything you need to assemble a stripped lower receiver. Just add your favorite stock kit for a complete lower receiver!

This MIL-SPEC parts kit is precision machined for a drop-in fit with nearly all lower receivers on the market. Features the Anderson Manufacturing stainless steel hammer and trigger set with a lightened speed hammer for improved lock time!

Kit includes:

  • (1) Stainless steel hammer
  • (1) Hammer spring
  • (1) Stainless steel trigger
  • (1) Trigger spring
  • (2) Hammer/trigger pins
  • (1) Disconnector
  • (1) Disconnector spring

  • (1) Bolt catch
  • (1) Bolt catch plunger
  • (1) Bolt catch roll pin
  • (1) Bolt catch spring

  • (1) Buffer retainer
  • (1) Buffer retainer spring

  • (1) Magazine catch
  • (1) Magazine catch button
  • (1) Magazine catch spring

  • (1) A2 pistol grip
  • (1) Pistol grip screw
  • (1) Pistol grip lock washer

  • (1) Standard safety selector
  • (1) Safety selector detent spring
  • (1) Safety selector detent

  • (1) Takedown pin
  • (1) Pivot pin
  • (2) Takedown/pivot pin detents
  • (2) Takedown/pivot pin springs

  • (1) Trigger guard
  • (1) Trigger guard roll pin

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BrandAnderson Manufacturing
Manufacturer.Anderson Manufacturing
Weight8 Oz
California Prop 65 warning

 WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information go to

First time AR build


Added this LPK to the budget Anderson stripped lower. Everything fit as expected. I just followed a YouTube how to video. Bought a DT stock kit as well. Now I just need an upper and I'm in business! Primary Arms is great. I just wish they were open a few hours on Saturday for the working man.

Everything l buy @ Primary Arms


As l expected, on time and exactly what I ordered. I've been doing business with them for two years now and they are a 5 star company.

Good fit, good finish


As with everything I have ordered from Primary, top quality and fast shipping.

Parts kit


Awesome service and shipping. Although i don't need it, I would have thought a parts list and instructions would have been included. No biggy.

good product at great price


best bet for basic builds.

Great Price, great service


Bought this and as always, have never been disappointed by any purchases made from primary arms. I recommend PA to all my friends

Great Parts


Came fast, fit well. Everything seems to work fine.

Lower parts kit


Everything is there and the workmanship looks to be very good.

TC Group


Exceptional quality at a value price. Would buy again!

Anderson lower parts kit


Fast shipper and received product as ordered. Will be doing buisness in the future.Thank You.