The "autonomist flag". Party flag of the Ludaks (Hlinka's Slovak People's Party) from 1938 to 1945, their paramilitary Organisation Hlinka Guard and their youth Organisation Hlinka Youth, variant
Own work

Vojtech Karpáty: Slovenská politická symbolika 1939–1945 [= The Slovak political symbolism 1939–1945]. In: Peter Sokolovič (Ed.): Od Salzburgu do vypuknutia Povstania. Slovenská republika 1939–1945 očami mladých historikov VIII [= From Salzburg to the breakout of the Uprising. The Slovak Republic 1939–1945 in the eyes of the young historians VIII]. Ústav pamäti národa, Bratislava 2009, ISBN 978-80-89335-21-3, p. 31–47.
Poster of the flag here and here.
Image of Gardist wearing the flag can be seen on this image and in the Slovak document Garda on Youtube here at 16:00.
Colored video of the flag from 0:02 here.
Fry1989, recoloured by NordNordWest