Originally used to haul freight trains, they are now used primarily on track maintenance trains and rolling stock transfer duties. As of 1 April 2014[update], all four locomotives are in service. Locomotives 601 and 602 are normally based at Inuyama Depot, and 603 and 604 are normally based at Shinkawa Depot.
The four locomotives were built by Toshiba between 1943 and 1945.
Locomotives DeKi 603 and 604 were originally built as locomotive numbers E401 and E402 for use on the Japanese-occupied island of Hainan during World War II, but were ultimately not able to be shipped abroad, and were instead purchased by Meitetsu.
Originally painted in black with yellow and black chevrons at the ends, the locomotives were repainted into "Meitetsu Blue" when they underwent life extension refurbishment in 1992.
^私鉄車両編成表 2014 [Private Railway Rolling Stock Formations - 2014] (in Japanese). Japan: Kotsu Shimbunsha. 24 July 2014. p. 102. ISBN978-4-330-48414-3.
^ abcdGoda, Tsuneo (May 2015). 私鉄・専用線機関車ウォッチング（19） [Private railway and industrial line locomotive watching (19)]. Japan Railfan Magazine (in Japanese) (Japan: Koyusha Co., Ltd.) 55 (649): p.90-92.CS1 maint: Extra text (link)
^ELダイヤ情報21 [Electric Loco Timetable Information 21] (in Japanese). Tokyo, Japan: Kotsu Shimbunsha. October 2012. p. 61. ISBN978-4330320120.
^名古屋鉄道EL120形 [Meitetsu Class EL120]. Japan Railfan Magazine (in Japanese) (Japan: Koyusha Co., Ltd.) 55 (649): p.55-57. May 2015.CS1 maint: Extra text (link)