The Avorio-Prassone balloon was developed in Italy during WWI but, due to its outstanding design and stability, was adopted elsewhere, including for Britain's Barrage Balloons.

 

Avorio-Prassione AP

Volume: 960 cu.m / 1130 cu.m / 1400 cu.m

Diameter: 10,72 m / 11,46 m / 12,17 m

Length: 20,92 m / 22,42 m / 23,81 m

Max wind: 20-25 m/sec