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AT3 Billet Upper Receiver for AR-15

AT3™ Slick Side Upper | Billet Upper Receiver for AR-15


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Lifetime WarrantyOn All AT3 Brand Products

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.

Fast & Free Shipping On orders over $50

You will receive fast, free shipping for all orders over $50

Shipping cost is $7.99 for orders under $50. We ship with UPS or USPS, depending on the item.

Most orders received by 1pm CST ship the same day

You will receive an email with tracking information at the time of shipment. To expedite shipping, we may ship your order from multiple warehouses. Orders placed on weekends, holidays, or after 1pm will ship the following business day.

Tough, Sleek, and ready for the AT3 SPEAR M-LOK Handguard

Machined from billet aluminum, this unique slick-side upper receiver has no forward assist, includes a dust cover, and matches perfectly with AT3’s SPEAR handguards with anti-rotation features. This upper also features more material to surround your barrel extension than typical forged receivers, making it more ideal for precision. Matches with mil-spec lower receivers for a reliable fit. Made in the USA.


  • M4 Feedramps
  • .250 takedown pin holes
  • Low-profile brass deflector
  • Includes dust cover
  • No Forward Assist


  • MATERIAL: 6061-T6 billet aluminum
  • FINISH: Anodized Black, Magpul FDE Cerakote, Magpul Stealth Grey Cerakote, Magpul OD Green Cerakote, Prison Pink Cerakote
  • COMPATIBILITY: Perfect match for AT3 SPEAR Handguards, standard AR15/M16 bolt carriers, charging handles, and some other handguards.
  • WEIGHT: 7.1 oz

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Customer Reviews

Based on 18 reviews
Excellent fit and finish

Bought the matching handguard in fde and man are they the perfect look. Absolutely flawless finish, very smooth and detailed. Haven't seen very many uppers and handguards that are made to fit together like this with no gaps around the handguard and upper. Definitely recommend

Thanks for sharing your feedback, Devin. We're glad you're satisfied with your purchase. Cheers!
Exactly what was needed.

Spent days searching online for a slab-slick sided upper receiverand found that AT3 Tactical was exactly what I needed for my custom build. Good finish and quality part. Still waiting on the other parts to finish the piece.

Thanks for sharing your feedback, Matthew. We're glad you're satisfied with your purchase. Cheers!
Upper reciver

Good product fit lower perfectly. The FDE finish matches well. I really like the side of the upper being smooth it slims the rifle up a lot. Haven’t finished the build yet so haven’t put any rounds down range but overall look and fitment are great

Thanks for sharing your feedback, Zach. We're glad you're satisfied with your purchase. Cheers!

Fit great and looks even better!

Thanks for sharing your feedback, Earl. We're glad you're satisfied with your purchase. Cheers!

I like it enough to buy it for a young shooter something I own and shoot. MKB

Thanks for sharing your feedback, Michael. We're glad you're satisfied with your purchase. Cheers!