Also see: Pillbox Analysis
Similar to the Bunker, the Pillbox is actually the ultimate defensive structure. Nothing can destroy it, not even multiple Naval Artillery rounds. Therefore, it is great to use it when you're under heavy artillery fire. It costs as much as a bunker, but is larger.
But it has a MAJOR drawback: Soldiers can't see the battlefield from inside it, even though they sometimes fire at enemies when they ordered to concentrate fire. Due to this drawback, the Pillbox is not a good structure to keep a squad in although it can prevent your people from being hurt. Also, it blocks line of sight.
However, the troops inside a Pillbox cannot survive a direct hit from a V1 rocket or a German Flamethrower. If one of these comes into contact with units stored in the Pillbox, they will catch on fire. This isn't a glitch.
You can only build one pillbox per battlefield.
Some keep their signalers in it once they have high exp so they can call in support and not get killed (and have to get a new, slow calling signaler).
You can also build a "medic hut." That is a Pillbox with a few medics in it, then when your soldiers are harmed, you move them into the pillbox either one by one or multiple at a time. You then raise them to 100 HP and then move them back out onto the battlefield to resume normal combat roles.
Pillboxes are concrete dug-in guard posts, normally equipped with loopholes through which to fire weapons. Pillboxes are often camouflaged in order to conceal their location and to maximize the element of surprise. They may be part of a trench system, form an interlocking line of defence with other pillboxes by providing covering fire to each other (defence in depth), or they may be placed to guard strategic structures such as bridges and jetties. The French Maginot line built between the world wars consisted of a massive bunker and tunnel complex, but as most of it was below ground little could be seen from the ground level. The exception were the concrete blockhouses and pillboxes which were placed above ground to allow the garrison of the Maginot line to engage an attacking enemy. About 28,000 pillboxes and other hardened field fortifications were constructed in England in 1940 as part of the British anti-invasion preparations of World War II. About 6,500 of these structures still survive.
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