The most common heavy Flak weapon was the 88mm. This was a multipurpose weapon that served well as an anti-tank gun, artillery gun and Flak gun. The Flak 88mm required 10 people to operate it, later in the war this would be reduced to 8 people and it could fire 15-20 rounds of minute to a maximum altitude of 35,000 ft. For most of the war the heavy Flak weapons fired time-fused high-explosive shells. The Germans were unable to develop a workable proximity-fused shell. In 1943 controlled-fragmentation rounds were introduced for the 88 's. These rounds had grooves cut on the inside face of the casings, when the charge detonated the case broke up into a smaller number of larger fragments. This fragmentation round was far more effective against heavy bombers than the regular high explosive rounds.

A Flak battery was laid out in groups of two or three groups of 6 guns. Later in the war these were increased to 8 guns in each group. With the entry of the Americans into the daylight bombing raids and the increased pressure of night bombing raid the Germans would group two or three Flak batteries together with a single command post directing them to engage one target.