HK Army Hostile CTS Reflex Backpack Mechanical Markers and some from other manufacturers) Chest Neck Protectors and some from other manufacturers) but we would need to cut the shoulder down slightly for this to work so if you want that option be sure to mention it in the comments before we ship out the pump guide complete with a customizable Dot Matrix strips on either side The modular outer storage zipper pouch can be removed and attached to the front shoulder straps to be used in a chest rig style configuration Inner HPA Tank Storage compartment with two adjustable velcro straps to securely hold up to an 80 cubic inch HPA air system