Stag Arms A3 LH Flattop AR-15 Upper Receiver Assembly

Manufactured by Stag Arms
SKU: STAG310412
MPN: STAG310412
Manufactured by Stag Arms
1 Review

In Stock

Standard orders will ship out within 1 business day if ordered by 3:30 pm CST, Monday-Friday. FFL orders will ship within 5 business days or less as long as we have the information for the transfer destination.

For individual Officer, First Responder, and Military pricing please make sure you are logged in. Click here for details



The Stag Arms A3 LH Flat Top AR-15 Upper Receiver features left side ejection for left handed shooters. It is built to Mil-Spec allowing compatibility with aftermarket components. The A3 left hand upper receiver is made from high quality aluminum and a durable hardcoat anodized finish. Perfect for building a rifle for left handers.

  • Left side ejection
  • Mil-Spec dimensions
  • Assembled with port door and forward assist
  • Hardcoat anodized finish
See More


BrandStag Arms
Feed RampsM4
FinishHardcoat Anodized
Forward AssistAssembled with Forward Assist
Port DoorAssembled with Port Cover
Receiver Material7075-T6 Aluminum
T MarksT-Marked
California Prop 65 warning

 WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information go to

Ratings & Reviews

1 review

  • 4 stars
  • 0 reviews
  • 3 stars
  • 0 reviews
  • 2 stars
  • 0 reviews
  • 1 star
  • 0 reviews

Great quality

by -

I own a few of these left handed uppers, fit and finish were perfect. PA as usual got it here quick.