Not all the 100 mm howitzers were installed in casemates. Some batteries simply had no casemates and here the gun were installed in open platforms. During bombardments the howitzers were pushed back inside and parked in garages that were closed with two large armoured doors. This was the case with two batteries:

• Batteria Peluna (II Settore);
• Batteria Spegi (II Settore). This was a special case, because it consisted of the former Opera 9 and Opera H that had their entrances modernised to place the howitzers.

Both batteries were very simple. They had simple open emplacements of 5 m. x 5,50 m. for the howitzers that could later be replaced by concrete casemates. However the casemates were never constructed.