Sights for anti-aircraft guns are slightly modified. The front sight is adjusted for shooting not only by planes, but also by small ships (boats, yachts, etc.). The rear sight is absolutely useless in the game and redone for accurate shooting at a distance of 3000 meters.
Distances:
Internal ring 2000m (aim at the target)
The aim of the sight is 3000 m (exactly between the sharp corners)
Middle ring 4000m (set on target)
Text in the screenshot.
Purpose: fuel tug - tower
Distance of fire = 3000m
Aiming through the rear sight
The expenditure of 40 shells