Italy made its first heavy tank in WW1. It had a powerful gun and a 65/17 howitzer (65mm caliber and a 17 caliber long barrel). The first prototype was finished in around 1918, but only two were ever built. The Fiat 3000 was then built, which was a slightly improved version. It was first used in 1922. They were used until 1943. It was renamed the L5/21 in 1935.