I did some research on the UPC code for this rifle and it is a "carbine" length gas system. If you look very closely at the expanded picture of this rifle, you can just make out the gas block which is about half way down the 16" barrel. This is where a "carbine" gas block would be located. On a 16" barrel, a mid length gas block is much closer to the tip of the barrel. The difference to a shooter is the impulse time is shorter (less recoil) on a mid length (or rifle length) gas system. However, it is really a negligible difference between "carbine" and mid-length gas systems recoil.

Carbine Length Gas System see *****Specifications and Features:
Stag Arms LLC AR-15 Semi Auto Rifle STAG580023
Distributor Exclusive
Direct Gas Impingement Rifle
Right Hand Ejection System
5.56 NATO (accepts .223 Remington)
16" 4150 Steel Barrel (Chrome Lined) Manganese Phosphate Coated
1:7" Twist Rate
A2 Flash Hider
Forged 7075 T6 Aluminum with Type 3 Hard Coat Anodized Upper/Lower Receiver
Mil-Spec Manganese Phosphate coated, Chrome Lined M16 BCG
*********Carbine Length Gas System
Low Profile Gas Block
Mil-Spec Charging Handle
Stag 15 Free Float M-LOK Compatible Hand Guard
Mil-Spec A2 Pistol Grip
Mil-Spec Stock
Mil-Spec 30 Round Magazine
Mil-Spec 6 Position Carbine Receiver Extension
Mil-Spec Single Stage Trigger with Mil-Spec Trigger Guard
Overall Length 32.25" Collapsed/35.5" Extended
Overall Weight 6.3lbs
Matte Black Finish

Watson, no, this rifle has a "Carbine Length Gas System" with a Low Profile Gas Block.