High Quality Content by WIKIPEDIA articles! The 2 inch Medium Trench Mortar, also known as the 2-inch Howitzer, and nicknamed the "Toffee Apple" or "Plum Pudding" mortar, was a British SBML medium trench mortar in use in World War I from mid-1915 to mid-1917. The designation "2 inch" refers to the mortar barrel, into which only the 22-inch bomb shaft but not the bomb itself was inserted; the bomb itself was actually 9 inches (230 mm) in diameter and weighed 42 lb (19 kg), hence this weapon is more comparable to a standard mortar of approximately 5-6 inch bore.