SEK (Sidirodromoi Ellinikou Kratous, Hellenic State Railways) Class Θγ (or Class Thg; Theta-gamma) was a class of 2-8-0 steam locomotives ex-United States Army Transportation Corps S160 type. 27 locomotives were acquired in 1947; Θγ521–537 were coal burners, while Θγ551–560 were oil burners. In 1959, Italian Railways (Ferrovie dello Stato, FS) sold another 25, formerly Class 736, Nos 736.011/23/40/55/73/90/101/2/126/7/131/5/51/8/60/4/6/78/88/90/9/203/7/9/17 to SEK. These were renumbered Θγ571-95 in the same order.
Stock list
A few still survive in scrapyard condition. Four in Thessaloniki (Θγ 525, 535, 593), one in Tithorea depot (Θγ 576) and (Θγ 532 and Θγ 584) are at an unknown location. Θγ 575 is under overhaul at Tyseley Locomotive Works in Great Britain