There are two smaller pillboxes referred to as Fire Posts and these support the main pillbox, and enable the defensive team to spread out over the site but still remain secure in a defensive position. These two fire posts are essentially identical in size and shape but one is 'right handed' and the other is 'left handed.' Their walls are one foot thickness (30 centimetres) and constructed of two leaves of brick with a solid concrete core, at best this would only have been bulletproof. The four loopholes are made from precast sections comprising the top and bottom halves leaving a long horizontal slot for observation and defensive fire purposes.
Each entrance is protected by an anti ricochet wall and the guards would have to duck under the low door lintel to enter. 
Each entrance is protected by an anti ricochet wall and the guards would have to duck under the low door lintel to enter.
Fire Post number 1 overlooking the factory buildings to the North in the distance.
Fire Post number 1 showing the entrance, this photo faces South.
Fire Post number 1. This photo faces East, in the distance can be seen the original fencing and a large gate for entry to the site.
This telephone box is located to the North side of Fire Post number 1. It shows they must have had good communications between the boxes.
Fire Post number 1 with the two storey type 24 pillbox just behind it. In the foreground is a water filled hollow, which may indicate the presence of a supporting slit trench during the war period.
