HK91, G3 Folding Stock - HDA3

HDA3 Folding Stock for HK91, G3

The HDA3 is a modular, USA-made stock system developed by Haga Defense and A3 Industries. Built for strength, adaptability, and cross-platform compatibility, it delivers premium rigidity, smooth adjustability, and long-term durability.

Features:

• Folding Steel Hinge: Heavy-duty steel hinge locks solidly in both open and folded positions. Folds left at a 3.5° cant.
• Reinforced Construction: All-metal internal components, including an aluminum cheek-riser button and length-adjustment latch, integrated into an extruded aluminum spine secured to the steel hinge.
• Adjustability: Length adjusts in 0.5" increments across 7 positions. Cheek riser offers 3 positions (0, +0.25", +0.50"). Both are one-hand operable.

Specifications:

• Material: 6061 hard-coat anodized aluminum adapter
• Polymer Components: 30% glass-fiber reinforced nylon
• Adapter Dimensions: 2.625" H × 1.5" W
• Buffer: Choate buffer included
• Length: 7.91"–10.91"
• Hinge: Nitride-coated 17-4 stainless steel, left-folding
• Extension: 7-position 6061 aluminum extrusion with 7075 locking latch
• Cheek Riser: 3-position polymer riser with anodized aluminum button
• Buttpad: Textured Santoprene TPE (stock configuration) 
• Sling Mounts: Rear sling loop, two steel QD points on the stock, plus three QD mounts on the adapter

Compatible With:

• HK91, G3
• Rifles using the same style end cap (PTR91, PTR-PDW, HK33, HK53, HK93, etc.)