Imperial Bunkers are a type of Imperial defensive fortification. Imperial Bunkers are built to protect troops as they defend strategic battlefield locations. These bulwarks can withstand an impressive amount of firepower, but they typically lack automated weapons systems of their own.
As such, they must be garrisoned to provide an effective defence, yet – as many enemy commanders have learned to their cost – a single fire team protected behind a bunker’s walls can reap a disproportionately heavy toll on approaching forces. Many Imperial Bunkers are built as forward observation posts and are often equipped with extensive vox units and comms arrays. Typically constructed on sites with commanding views, the better to monitor the movement of enemy units, these bunkers are especially valued by frontline Imperial Guard officers who prefer to issue orders, direct artillery strikes and coordinate troop deployments from the relative safety of an armoured fortification.
Half a Bastion in almost every way. Cheaper, but lower transport, fire points, toughness, and wounds. Also, no heavy bolters. However, it's half the cost and a reasonable alternative to 10-manning a devastator squad (particularly if you're Long Fangs or Dark Reapers who can't 10-man at all).