 The Germans made considerable use of the weapon ("Flammenwerfer" 35) during their invasion of the Netherlands and France, against fixed fortifications.World War II German army flamethrowers tended to have one large fuel tank with the pressurizer tank fastened to its back or side.Some German army flamethrowers occupied only the lower part of its wearer's back, leaving the upper part of his back free for an ordinary rucksack.