This is a Magpul Industries Stock known as the PRS-Precesion Rifle/Sniper Sto, model MAG340-BLK.
The Magpul PRS2 (Precision Rifle/Sniper) - G3 Model is a drop-in" precision-adjustable butt stock especially designed for the HK G3/91 rifle and its variants. Designed to offer the fine-tuned" customized feel of a precision target stock" the PRS2 is adjustable for both cheek riser height and length-of-pull without sacrificing the durability necessary to withstand the operational environment. Compared to common plastic fixed stocks" the PRS2 has a similar minimum LOP but can extend up to 1.25" longer. Machined aluminum adjustment knobs feature positive-locking click detents to maintain position under recoil and allows easy" tool-less adjustments by simply rotating the knobs. Machined aluminum butt-plate and alloy steel adjustment shafts provide stability and strength to withstand severe impact conditions. Rubber butt-pad offers positive shoulder purchase to prevent slippage for optimal accuracy even with body armor or modular gear. Stronger and heavier than most OEM stocks" the PRS2 also adds beneficial weight to the rear of normally nose-heavy G3/91 rifles.
Features:
Direct replacement for any 7.62x51 HK variant that has a factory fixed-stock steel backplate and standard buffer (NOT the HK heavy buffer)