Lower Parts Kit for AR-15
From complete kits to individual pieces, AT3 has the lower parts you need to build your ultimate AR-15.
We provide high-quality lower receiver parts kit, safety selector, and mag release.
Sort
Filter
Show In-Stock Only?
Price
Brand
- Lower Receiver Parts - AT3 Tactical (49)
- Lower Receiver Parts - Strike Industries (21)
- Lower Receiver Parts - Battle Arms Development (11)
- Lower Receiver Parts - Radian Weapons (9)
- Lower Receiver Parts - Timber Creek (8)
- Lower Receiver Parts - CMMG (8)
- Lower Receiver Parts - Armaspec (8)
- Lower Receiver Parts - Odin Works (7)
- Lower Receiver Parts - Phase 5 (6)
- Lower Receiver Parts - Magpul (6)
- Lower Receiver Parts - Aero Precision (6)
- Lower Receiver Parts - Luth-AR (4)
- Lower Receiver Parts - LBE Unlimited (4)
- Lower Parts - Fortis (4)
- Lower Receiver Parts - Sons of Liberty Gun Works (3)
- Lower Receiver Parts - KE Arms (3)
- Lower Receiver Parts - JP Enterprises (3)
- Lower Receiver Parts - Ergo (3)
- Lower Receiver Parts - Tyrant CNC (2)
- Lower Receiver Parts - Troy (2)
- Lower Receiver Parts - Mission First Tactical (2)
- Lower Receiver Parts - Kaw Valley Precision (2)
- Lower Receiver Parts - KAC (2)
- Lower Receiver Parts - Badger Ordnance (2)
- Lower Receiver Parts - B5 Systems (2)
- Lower Receiver Parts - Arms Unlimited (2)
- Lower Receiver Parts - Anderson (2)
- Lower Receiver Parts - Yankee Hill Machine (1)
- Lower Receiver Parts - Wilson Combat (1)
- Lower Receiver Parts - Timney Triggers (1)
- Lower Receiver Parts - Rise Armament (1)
- Lower Receiver Parts - KNS Precision (1)
- Lower Receiver Parts - Guntology (1)
- Lower Receiver Parts - Geissele (1)
- Lower Receiver Parts - Elftmann Tactical (1)
- Lower Receiver Parts - CMC Triggers (1)
- Lower Receiver Parts - Bravo Company (1)
Caliber
Color
- Lower Receiver Parts - Black (109)
- Lower Receiver Parts - Flat Dark Earth (52)
- Lower Receiver Parts - Red (43)
- Lower Receiver Parts - Blue (38)
- Lower Receiver Parts - OD Green (37)
- Lower Receiver Parts - Gray (30)
- Lower Receiver Parts - Tungsten (21)
- Lower Receiver Parts - Burnt Bronze (19)
- Lower Receiver Parts - Pink (16)
- Lower Receiver Parts - Titanium (14)
- Lower Receiver Parts - Purple (10)
- Lower Reciever Parts - Silver (10)
- Lower Receiver Parts - Gold (5)
- Lower Receiver Parts - Stainless (4)
- Lower Receiver Parts - Tan (3)
- Lower Receiver Parts - Brown (2)
- Lower Receiver Parts - NP3 (1)
List
Grid
-
AT3™Sale!
AT3™ FU-BAG™ AR-15 Lost Parts Kit – Springs, Detents, Replacement Components
Made an "Oops" with your New Build? You Detent-Launchin', Spring-Losin' Fool, you. We've all been there. Whether it's rolling the dice on that bargain bin LPK in your local...2 Options -
AT3™Sale!
AT3™ Mil-Spec AR-15 Pivot Pin/Takedown Pin Detent Springs – Set of 2
AT3™ Mil-Spec AR-15 Pivot Pin/Takedown Pin Detent Springs - Set of Two All AT3 Tactical lower receiver parts meet or exceed Mil Spec. These parts are guaranteed to fit and... -
AT3™Sale!
AT3™ MOTHERFU-BAG™ – The BIG AR-15 Lost Parts Kit – Springs, Detents, Wear Parts,...
Launch a detent? Snap a spring? Don't get mad, just fix it with this AR-15 Lost Parts Kit! Alright, so y'all seem to like the FU-BAG. Like a lot. Which... -
AT3™Sale!
AT3™ Castle Nut for AR-15 Buffer Tubes – 10 Colors Available
Secure Your AR15 Buffer Assembly with a Steel Castle Nut This steel castle nut is an essential piece of an AR15 buffer tube/stock assembly. With standard cuts for use with...10 Options -
AT3™Sale!
AT3™ Mil-Spec AR-15 Buffer Retainer Spring
Mil-Spec AR-15 Buffer Retainer Spring All AT3 Tactical lower receiver parts meet or exceed Mil Spec. These parts are guaranteed to fit and function in your AR buffer assembly and... -
AT3™Sale!
AT3™ Mil-Spec AR-15 Selector Detent
Mil-Spec AR-15 Selector Detent All AT3 Tactical lower receiver parts meet or exceed Mil Spec. These parts are guaranteed to fit and function in your AR safety assembly and are... -
AT3™Sale!
AT3™ Mil-Spec AR-15 Bolt Catch Spring
Mil-Spec AR-15 Bolt Catch Spring All AT3 Tactical lower receiver parts meet or exceed Mil Spec. These parts are guaranteed to fit and function in your AR lower receiver and... -
AT3™Sale!
AT3™ Mil-Spec AR-15 Selector Detent Spring
Mil-Spec AR-15 Selector Detent Spring All AT3 Tactical lower receiver parts meet or exceed Mil Spec. These parts are guaranteed to fit and function in your AR mag catch assembly... -
AT3™Sale!
AT3™ Mil-Spec AR-15 Bolt Catch Plunger
Mil-Spec AR-15 Bolt Catch Plunger Looking for a high-quality bolt Catch Plunger for your AR-15? Look no further than AT3 Tactical. Our Bolt Catch Plunger is designed to meet or... -
AT3™Sale!
AT3™ Mil-Spec AR-15 Buffer Retainer
AT3 Tactical Mil-Spec AR-15 Buffer Retainer If you're looking for a reliable buffer retainer for your AR-15, look no further than the Mil-Spec AR-15 Buffer Retainer from AT3 Tactical. Made... -
10% Off!
Strike Industries AR-10 Enhanced Lower Receiver Parts Kit
Elevate Your Build with the Strike AR-10 Enhanced Lower Parts Kit Upgrade your AR-10 lower receiver with the Strike Industries Enhanced Lower Receiver Parts kit, featuring essential components for a... -
10% Off!
Strike Industries AR MAGSTOP Fixed Magazine Converter
Legally Store Your AR with This Cost-Effective Solution The Strike Industries AR MAGSTOP provides a simple way to configure your AR-15 or AR-10 for legal fixed magazine storage per certain... -
10% Off!
Strike Industries HEX 60-90 Degree Selector Switch for AR-15
Your Choice - Strike Industries HEX 60/90° Selector Switch Customization is key with the Strike Industries HEX 60/90° Ambidextrous Selector Switch for AR-15s. This versatile upgrade lets you choose between... -
10% Off!
Strike Industries Modular Bolt Catch for AR-15
Strike Industries Modular AR Bolt Catch This modular bolt catch lets you easily swap between 4 different button styles - standard, oversized, left extended, and right extended. No need to... -
AT3™Sale!
AT3™ Mil-Spec AR-15 Magazine Catch Spring
Mil-Spec AR-15 Magazine Catch Spring All AT3 Tactical lower receiver parts meet or exceed Mil Spec. These parts are guaranteed to fit and function in your AR mag catch assembly... -
10% Off!
Strike Industries Pistol Grip Plug Tool Holder Insert
Handy Tool Hideaway - The Strike Pistol Grip Tool Holder Transform your grip into a discreet tool caddy with the Strike Pistol Grip Plug Tool Holder Insert. This nifty drop-in... -
AT3™Sale!
AT3™ Mil-Spec AR-15 Pistol Grip Screw
AT3 Mil-Spec AR-15 Pistol Grip Screw Looking for a reliable replacement for your lost or damaged AR-15 Pistol Grip Screw? Look no further than AT3 Tactical. Our Mil-Spec AR-15 Pistol... -
AT3™Sale!
AT3™ Mil-Spec AR-15 Pistol Grip Lock Washer
Mil-Spec AR-15 Pistol Grip Lock Washer If you're looking for a Pistol Grip Lock Washer that meets or exceeds Mil-Spec, look no further than AT3 Tactical. Our lock washers are... -
AT3™Sale!
AT3™ Mil-Spec AR-15 Bolt Catch Pin
Mil-Spec AR-15 Bolt Catch PIN Looking for a high-quality Bolt Catch Pin for your AR-15? Look no further than AT3 Tactical. Our bolt catch pin is designed to meet or... -
AT3™Sale!
AT3™ Mil-Spec AR-15 Disconnector Spring
Mil-Spec AR-15 Disconnector Spring Looking for a durable and reliable Disconnector Spring for your AR-15 trigger? Look no further than AT3 Tactical. Our Disconnector Spring is designed to meet or... -
AT3™Sale!
AT3™ Mil-Spec AR-15 Trigger Guard Roll Pin
Mil-Spec AR-15 Trigger Guard Roll Pin All AT3 Tactical lower receiver parts meet or exceed Mil Spec. These parts are guaranteed to fit and function in your AR trigger guard... -
AT3™Sale!
AT3™ Mil-Spec AR-15 Hammer/Trigger Pins – 2 Pcs
Mil-Spec AR-15 Hammer/Trigger Pins (2 Pieces) All AT3 Tactical lower receiver parts meet or exceed Mil Spec. These parts are guaranteed to fit and function in your AR trigger assembly... -
10% Off!
Strike Industries Extended Bolt Catch for AR15
A "Go Fast" Addition To Your Next Build The Strike Industries Extended Bolt Catch is a heavy-duty and reliable upgrade that makes your AR-15 quicker and easier to operate. It... -
AT3™Sale!
AT3™ AR 15 Enhanced Lower Parts Kit with Nickel Teflon Trigger – No Grip...
Tired of swapping out parts? Build the lower you actually want. This premium lower parts kit features our AT3 Enhanced Nickel Teflon Trigger, giving you the quality trigger your rifle...
Other Lower Receiver Components for AR 15:
AR 15 Buffer Tube Parts (Receiver Extension)
AR-15 Triggers
Buttstocks
Lower Parts Kit for AR-15
Magazines & Parts
Pistol Grips
AR-15 Trigger Guards