AT3 Tactical
AT3 Tactical
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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.

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Lower Receiver Part Kits Safety Selector Mag Release Bolt Catch Pivot & Takedown Pins Trigger Guards Other Lower Parts
267 products

AT3™ FU-BAG™ AR-15 Lost Parts Kit – Springs, Detents, Replacement Components
2 options
(550)
from $8.99
In stock
10% offAT3 Tactical Castle Nut for AR15

AT3™ Castle Nut for AR-15 Buffer Tubes – 9 Colors Available
+19 options
(105)
$4.99from $4.49
In stock

AT3™ Pro-Builder™ AR-15 Lower Parts Kit – No Grip or Trigger Assembly
RECOMMENDED
+19 options
(130)
from $31.99
In stock
10% offAT3 Pro-Builder AR-15 Lower Build Kit

AT3™ Pro-Builder™ Black AR-15 Lower Build Kit
(3)
$74.99$67.49
In stock
8% offGeissele Automatics Maritime Extended Bolt Catch - AT3 Tactical

Geissele Automatics Maritime Extended AR-15 Bolt Catch
(11)
$31.00$28.52
In stock
10% offCMMG ZEROED Extended Bolt Catch for AR-15

CMMG ZEROED Extended Bolt Catch for AR-15
DAILY DEAL
(2)
$12.60$11.34
In stock
10% offCMC Triggers Anti-Walk AR-15 Trigger Pin Set - Small

CMC Triggers Anti-Walk AR-15 Trigger Pin Set – Small
(3)
$13.99$12.59
In stock
10% off

Arms Unlimited Enhanced Ambidextrous AR-15 Magazine Release
(3)
$40.00$36.00
In stock
8% offCMMG ZEROED Ambidextrous Magazine Catch for AR-15

CMMG ZEROED Ambidextrous Magazine Catch for AR-15
$32.36$29.77
In stock
10% off

Geissele Ultra Duty AR-15 Mag Release Button
DAILY DEAL
(1)
$13.00$11.70
In stock
10% offRise Armament AR-15 Lower Parts Kit - No Grip - No Trigger Guard - Black

Rise Armament AR-15 Lower Parts Kit – No Grip – No Trigger Guard – Black
$44.99$40.49
In stock
10% offJP Enterprises 3.5lb Reduced Power Trigger Spring Kit for AR-15

JP Enterprises 3.5lb Reduced Power Trigger Spring Kit for AR-15
(4)
$11.95$10.76
In stock
25% offAT3™ Mil-Spec AR-15 Hammer Spring

AT3™ Mil-Spec AR-15 Hammer Spring
(2)
$3.49$2.62
In stock
12% offCMMG .308 GunBuilder Lower Receiver Parts Kit- No Grip or Fire Control Group

CMMG .308 GunBuilder Lower Receiver Parts Kit- No Grip or Fire Control Group
(2)
$58.99$51.91
In stock
12% offGeissele Posi-Snap AR-15 Safety Selector

Geissele Posi-Snap AR-15 Safety Selector
$37.00$32.56
In stock
AT3 Tactical AR-15 Ultimate Cerakote Color Upgrade Kit - Flat Dark Earth

AT3 Tactical AR-15 Ultimate Cerakote Color Upgrade Kit
8 options
(10)
from $123.99
In stock

AT3™ GI Mil-Spec 6lb Single-Stage AR-15 Trigger – Flat or Curved
2 options
(21)
from $32.99
In stock

AT3™ MOTHERFU-BAG™ – The BIG AR-15 Lost Parts Kit – Springs, Detents, Wear Parts, and More
(41)
$21.99
In stock
35% offAT3 Safety Selector - Ambi - Multiple Colors

AT3™ Ambidextrous AR-15 Safety Selector – 9 Colors Available
DAILY DEAL
+19 options
(75)
$27.99from $18.19
In stock

Amend2 Enhanced Trigger Guard – AR-15 / AR-10 – Multiple Colors
NEW
2 options
from $7.99
In stock
AT3™ Mil-Spec AR-15 Pivot Pin/Takedown Pin Detent Springs - 2 Pcs

AT3™ Mil-Spec AR-15 Pivot Pin/Takedown Pin Detent Springs – Set of 2
(44)
$1.49
In stock
10% off

AT3™ AR-15 Enhanced Billet Trigger Guard Assembly
RECOMMENDED
+19 options
(19)
from $11.49
In stock
Up to 20% off

AT3™ AR-15 Mil-Spec Bolt Catch – 9 Colors Available
+19 options
(23)
$7.49from $6.59
In stock
Rise Armament RAVE 140 3.5 Pound Single Stage Drop-In Trigger - Includes Anti-Walk Pins & Lower Parts Kit - No Grip - No Trigger Guard - Flat or Curved

Rise Armament RAVE 140 3.5 Pound Single Stage Drop-In Trigger – Includes Anti-Walk Pins & Lower Parts Kit – No Grip – No Trigger Guard – Flat or Curved
2 options
(2)
from $145.99
In stock
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