Abstract: A tactical upper garment for concealed carry of a weapon has an interior portion and an exterior portion. A weapon retention mounting patch is affixed to the interior portion, and a detachable firearm holster is removably attachable to the weapon retention mounting patch. The holster can be loaded with a firearm and then moved from a location outside the exterior portion to a space inside the interior portion. The detachable firearm holster is movable within said space along a height and a width of the weapon retention mounting patch to a desired position. The detachable firearm holster is pressed against the weapon retention mounting patch at the desired position to attach the detachable firearm holster to the tactical upper garment at the desired position.