AT3™ Slick Side Upper | Billet Upper Receiver for AR-15
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Product description
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. This lower matches up with mil-spec lower receivers for a secure, reliable fit.
The AT3 Slick Side Upper Receiver also comes in a wide variety of colors, ranging from classic black, Magpul-matching Flat Dark Earth, vivid Pink, USMC Red, and even new metallic shades like Tungsten, Titanium, and Burnt Bronze. Flat black uppers have classic hard-coat anodizing, while the other colors receive a durable Cerakote finish.
Features:
- M4 Feedramps
- .250 takedown pin holes
- Low-profile brass deflector
- Includes dust cover
- No Forward Assist
Specifications:
- Platform: AR15
- Material: 6061-T6 billet aluminum
- Finish
- Black: Type III Hardcoat Anodized
- Flat Dark Earth: H-267 Magpul® Flat Dark Earth
- OD Green: H-232 Magpul® OD Green
- Pink: H-224 SIG™ Pink
- Burnt Bronze: H-148 Burnt Bronze
- Tungsten: H-237 Tungsten
- Titanium: H-170 Titanium
- Red: H-167 USMC Red
- Compatibility: Perfect match for AT3 SPEAR Handguards, standard AR15/M16 bolt carriers, charging handles, and some other handguards.
- Weight: 7.1 oz
Note: Not compatible with Wheeler Delta Series Upper Vise Block. We suggest to use the Magpul Bev Block
All 8 options on this page
- AT3™ Slick Side Upper | Billet Upper Receiver for AR-15 - Color: Black SKU AT3-UPPER-1 · UPC 783935100921
- AT3™ Slick Side Upper | Billet Upper Receiver for AR-15 - Color: Red SKU AT3-UPPER-RED · UPC 5060748423382
- AT3™ Slick Side Upper | Billet Upper Receiver for AR-15 - Color: Burnt Bronze SKU AT3-UPPER-BB · UPC 5060748421128
- AT3™ Slick Side Upper | Billet Upper Receiver for AR-15 - Color: Tungsten SKU AT3-UPPER-TG · UPC 5060748421814
- AT3™ Slick Side Upper | Billet Upper Receiver for AR-15 - Color: Titanium SKU AT3-UPPER-TI · UPC 5060748421098
- AT3™ Slick Side Upper | Billet Upper Receiver for AR-15 - Color: Pink SKU AT3-UPPER-PNK · UPC 783935100969
- AT3™ Slick Side Upper | Billet Upper Receiver for AR-15 - Color: Flat Dark Earth SKU AT3-UPPER-FDE · UPC 783935100938
- AT3™ Slick Side Upper | Billet Upper Receiver for AR-15 - Color: OD Green SKU AT3-UPPER-ODG · UPC 783935100952
Customer reviews 138
Verified buyer Also functions as needed. No issues on the function side.
Questions & Answers 10
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Will it fit an ATI Ar-15?
Michael · Jul 15, 2026AT3 Support Team — Yes, it will fit your ATI AR-15 as long as your lower receiver uses standard mil-spec pin locations and dimensions.
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I just want to be clear that this i compatible with free floating handrail barrel nuts?
Ryan · Jul 10, 2026AT3 Support Team — Yes, it is completely compatible with standard free-float handguard barrel nuts because its face uses the exact same universal threads as any mil-spec AR-15 upper receiver.
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will this work with the samson star rail?
jon · Dec 11, 2025AT3 Support Team — No, the AT3™ Slick Side Upper will not reliably work with the Samson Star Rail.
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am i able to use this upper receiver with a stngr HWK™ M-LOK FREE FLOAT HANDGUARD 13.5"
Emanuel Torres · Jun 27, 2025AT3 Support Team — Yes, you can use the AT3™ Slick Side Billet Upper Receiver for AR-15 with the Stngr HWK™ M-LOK Free Float Handguard 13.5"
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.
