The Italian A4 Bomb was an Anti-personnel, air dropped bomb developed and used by Italy in World War II. Called The ''Thermos'' Bomb – for it's resemblance to the vacuum flask still in popular usage throughout The World, it was somewhat of a dangerous failure. 12-Inches long and weighing 8-pounds, The AR4 carried over 1-pound of TNT explosive. A timed delay fuse would activate the charge, which was effective up to 115-feet. Multiple devices were dropped via plane over Enemy Troop concentrations.
Unfortunately, The AR4 was extremely sensitive and could detonate at the slighted jarring. This caused premature explosions and often loss of aircraft. In most cases, The AR4 was armed while in flight – but even this was a dangerous and problematic issue. Later in The War, a better and somewhat more psychologically impactful version was made. This version had a better casing with more explosive stability. The fusing was programmed to not detonate for up to 80-hours after being dropped.