The HK Army Alpha Air Tank Builder lets you put together your own complete air system, one order at a time. Choose your carbon fiber bottle size and the regulator that matches your setup, and it ships to you as one matched, ready-to-fill system — no guessing whether parts picked separately will actually work together. Every bottle in the HK Army Alpha Air line uses the same lightweight carbon fiber construction and 4500psi rating, whichever size you choose, and it's available in a wide range of color finishes. Pick your capacity, pick your regulator, and you're set. HK Army Alpha Air Tank Builder Key Features Fully custom system — choose your bottle size and regulator in one order Five bottle sizes to choose from: 48ci, 68ci, 77ci, 88ci, and 98ci Four regulator options: Standard, HP8, MP5, and Turbine Pro Same lightweight carbon fiber construction across the entire Alpha Air line, rated to a 4500psi fill Ships as one complete, ready-to-fill system Available in a wide range of color finishes Choose Your Bottle Size 48ci — The most compact bottle in the Alpha Air lineup, for players who want the lightest possible footprint on their marker. 68ci — HK Army's lightest carbon fiber bottle to date, a popular size for tournament and speedball setups. 77ci — The middle capacity in the lineup, adding more air without much extra size or weight. 88ci — A step up in capacity for players who'd rather carry more air than swap tanks mid-day. 98ci — The largest bottle in the Alpha Air line, built for scenario days and extended ops without a refill. Choose Your Regulator Standard — HK Army's base 800psi output regulator, a simple and reliable way to get a complete system running. HP8 — A 700–800psi output regulator, built from aircraft-grade aluminum with a full-color gauge and dual O-rings for a secure seal. MP5 — A fixed 450–550psi output regulator, sharing the same aircraft-grade aluminum construction as the HP8. Turbine Pro — HK Army's rotational, adjustable regulator, tunable across a 350–650psi range for players who want to fine-tune their output. Already Have a Regulator? If you already own a compatible regulator, you don't need to buy another one through the Tank Builder — each Alpha Air size is also sold as a bottle-only listing, and any HK Army regulator will fit, along with regulators from Ninja, Immortal Air, and Empire. Frequently Asked Questions How does the Tank Builder work? Pick your Alpha Air bottle size — 48ci, 68ci, 77ci, 88ci, or 98ci — and your regulator — Standard, HP8, MP5, or Turbine Pro — and we'll put them together and ship you one complete, ready-to-fill air system. What's the difference between the regulator options? Standard runs a fixed 800psi output. HP8 runs a 700–800psi output. MP5 runs a fixed 450–550psi output. Turbine Pro is rotational and adjustable across a 350–650psi range for players who want to fine-tune their output rather than run a fixed setting. Which bottle size should I choose? It comes down to how much air you want between fills versus how much size and weight you want on your marker. The 48ci is the smallest and lightest bottle in the lineup, the 68ci and 77ci step up in capacity while staying compact, and the 88ci and 98ci trade more length and weight for extra air. Can I buy just the bottle without a regulator? Yes. Each Alpha Air size is also available as a bottle-only listing if you already have a compatible regulator, and any HK Army regulator will fit, along with regulators from Ninja, Immortal Air, and Empire. Will this system work with my marker? Yes. Every Alpha Air bottle uses a standard tank valve thread, and each regulator option threads onto a marker's ASA the same way most paintball regulators do, so this system works with virtually any paintball marker. Does the system come filled with air? No. Like all paintball air systems, this ships empty. You'll need to fill it at a certified air station or field once it arrives, up to its rated 4500psi capacity.