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AT3 Billet Upper Receiver for AR-15

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


MSRP: $89.99


Out Of Stock

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
  • 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 13 reviews
You cannot beat the looks of the Slick Side

I have never liked the "Forward Assist" hanging out the side of the receiver. My two Sporters never needed it, neither the one I had in the Army. If it didn't chamber, something is wrong, fix it. I look forward to taking this Slick Side to the range.

Thanks for sharing your feedback, Alden. We're glad you're satisfied with your purchase. Cheers!
Slick side upper

Built a upper using only AT3 parts fit will be ordering more soon

Thanks for sharing your feedback, Kevin. We're glad you're satisfied with your purchase. Cheers!
Sleek and sexy

Great upper. Looks even better with spear handguard. Favorite build todate. Great price forwhar your buying. Love the minimalist design

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

The fact it has compatibility with "some other handguards" is stated in the description, but the receiver seems almost designed not to fit many common aftermarket handguards. Given the price, I took a gamble on if the Odin Works handguards I had would fit or not. They didn't. I had to mill the back end of the guards down a bit but I got it work. That's on me, and won't necessarily stop me from buying these again, but I think it should be a bit more clearly stated or emphatic that fitment issues will likely be common in the description.

I also found the finish to be a bit rough and coarse around the barrel threads. It resolved itself after threading barrel nut on and removing it a few times without torquing it down.

Again, there is nothing that would make me not recommend the product. 4/5

Thanks for sharing your feedback, Customer1776. We're glad you're satisfied with your purchase. Cheers

This will be the only upper i use from now on absolutely fantastic! I now have one in black for my wilson combat 300 ham’r build and one in fde for my 223 wylde do all rifle. But seriously these are the only uppers i will use from now on thanks at3

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