AT3™ Mil Spec Buffer Tube Kit For AR-15 - 9 Colors Available
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From orders that included this itemProduct description
The perfect kit for your next build – at a price that can’t be beat.
This Mil-Spec AR-15 Buffer Tube Kit includes the buffer tube, castle nut, lock plate, 3oz carbine recoil buffer and recoil spring. All parts are designed for easy assembly and compatibility with all your other AR-15 components. And if you want to get a custom look for your gun, we offer an array of Cerakote finish options to match the buffer tube, castle nut, and endplate.
This kit and its components are backed by the AT3 Lifetime Warranty for guaranteed function. AT3 cannot warranty against Cerakote™ inconsistencies or the wearing of coatings over time.
Included in the kit
- 6 position Mil-Spec buffer tube
- 3oz carbine recoil buffer with T6 anodized aluminum body
- Steel Buffer Spring
- Steel castle nut
- Steel end plate
Specifications
- Buffer Tube Diameter: 1.146″ (Mil Spec)
- Buffer Tube Length: 7 1/4″
- Buffer Tube Thread type: 1 3/16-16 UN-3B SPECIAL
- Buffer Tube Material: 6061-T6 Aluminum
- Spring Type: Carbine length, black coated
- Castle nut material: Steel
- End plate material: Steel
- Recoil spring type: Steel
- Finish
- Black: Hardcoat Anodized
- Flat Dark Earth: H-267 Magpul® Flat Dark Earth
- OD Green: H-232 Magpul® OD Green
- Pink: H-224 SIG™ Pink
- Red: H-167 USMC Red
- Blue: H-171 NRA Blue
- Burnt Bronze: H-148 Burnt Bronze
- Tungsten: H-237 Tungsten
- Titanium: H-170 Titanium
- Buffer type: 3oz weight, carbine style
All 9 options on this page
- AT3™ Mil Spec Buffer Tube Kit For AR-15 - 9 Colors Available - Color: Black | SKU: BTKIT-01-MILSPEC
- AT3™ Mil Spec Buffer Tube Kit For AR-15 - 9 Colors Available - Color: Burnt Bronze | SKU: BTKIT-01-MILSPEC-BB
- AT3™ Mil Spec Buffer Tube Kit For AR-15 - 9 Colors Available - Color: Tungsten | SKU: BTKIT-01-MILSPEC-TG
- AT3™ Mil Spec Buffer Tube Kit For AR-15 - 9 Colors Available - Color: Flat Dark Earth | SKU: BTKIT-01-MILSPEC-FDE
- AT3™ Mil Spec Buffer Tube Kit For AR-15 - 9 Colors Available - Color: Titanium | SKU: BTKIT-01-MILSPEC-TI
- AT3™ Mil Spec Buffer Tube Kit For AR-15 - 9 Colors Available - Color: OD Green | SKU: BTKIT-01-MILSPEC-ODG
- AT3™ Mil Spec Buffer Tube Kit For AR-15 - 9 Colors Available - Color: Pink | SKU: BTKIT-01-MILSPEC-PNK
- AT3™ Mil Spec Buffer Tube Kit For AR-15 - 9 Colors Available - Color: Red | SKU: BTKIT-01-MILSPEC-RED
- AT3™ Mil Spec Buffer Tube Kit For AR-15 - 9 Colors Available - Color: Blue | SKU: BTKIT-01-MILSPEC-BLU
Customer reviews 93
AT3 Tactical · Thanks, Jason! Glad the buffer tube color matched perfectly. Sorry the spring felt weak—we'll pass that along. Check out the Armaspec SRS for your next upgrade!
AT3 Tactical · Thank you for taking the time to leave a review. We're glad to hear that you're enjoying our AT3™ Mil Spec Buffer Tube Kit for your AR-15. If you ever have any questions or feedback, please don't hesitate to reach out. Happy shooting!
AT3 Tactical · Thank you for leaving a review for our AT3™ Mil Spec Buffer Tube Kit. We're glad to hear that you found the quality to be good. We apologize that the FDE coloring was not consistent with other brands you have used. Our team is constantly working on improving and perfecting our products, so we appreciate your feedback. If there is anything else we can assist you with, please don't hesitate to reach out.
Questions & Answers
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Warranty & returns
Backed by the AT3 Lifetime Warranty!

All AT3 Tactical Brand Products carry a lifetime warranty against manufacturer’s defects.
This includes AT3 Red Dot Sights, Handguards, Iron Sights, and any other product that carries the “AT3 Tactical” or “AT3™” name. For other brands (ex. Magpul or Troy), please refer to the manufacturer’s warranty policy.
In the event that your AT3™ product becomes unusable, we will repair or replace the product at no charge to you.
If we cannot repair your product, we will replace it with a product in perfect working order of equal or better physical condition. The warranty is fully transferable, but we may require information about the original purchase to validate the authenticity of the product.
If your product is in need of warranty service, please contact AT3 Tactical to start the process
Our contact info is available here. To expedite processing, please provide your order information and description of the defect.
Please note: The AT3 Lifetime Warranty does not cover loss, theft, intentional damage or cosmetic damage that doesn’t affect the performance of the product.
90-day no-hassle returns
The AT3 Tactical store has a 90 day no-hassle return policy for products in good condition. You can view the full details of our return policy here.
If you encounter an issue or defect with a product after 90 days of your purchase, you can refer to the manufacturer for a warranty claim. Their policies are below.


















