Flame tanks have been superseded by thermobaric weapons such as the Russian TOS-1. The idea for this tank was developed during World War I by British and French.
Although flame tanks cleared many cave defenses, there was no breakthrough, and the XXIV Corps suffered 720 casualties.
Upgunned versions with the 76 mm gun M1 and the 17-pounder were introduced to improve the M4's firepower, but concerns about protection remained—despite the apparent armour deficiencies, a total of some 42,000 Shermans were built and delivered to the Allied nations using it during the war years, a total second only to the T-34. Tank hulls were modified to produce flame tanks, mobile rocket artillery, and combat engineering vehicles for tasks including mine-clearing and bridging.
Some tanks were converted to flame tanks, specializing on close-in attacks on enemy strongholds with flamethrowers.
The vulnerability of infantry carrying backpack flamethrowers and the weapon's short range led to experiments with tank-mounted flamethrowers (flame tanks), which were used by many countries.
Italy employed man-portable flamethrowers and L3 Lf flame tanks during the Second Italo-Abyssinian War of 1935 to 1936, during the Spanish Civil War, and during World War II. The L3 Lf flame tank was a CV-33 or CV-35 tankette with a flamethrower operating from the machine gun mount.
These were known as SATAN flame tanks.