The Stridsvagn 103 (Strv 103), also known as the S-Tank, is a Swedish post-World War II main battle tank, designed and manufactured in Sweden. Developed in the 1950s, it was the first main battle tank to use a turbine engine and the only mass-produced tank since World War II to dispense with a turret. It has an unconventional design with a unique gun laying process: it is turretless with a fixed gun traversed by engaging the tracks (like the 75mm gun on the 1930s French Char B1) and elevated by adjusting the hull suspension.