They were active from 1919 to 1929. That´s all I could find so far. If you have a picture showing the radiator with emblem don´t hesitate to send it to me.
Both emblems are from the Lee Roy Hartung collection / Chicago that was up for auction in november 2011.
|large radiator emblem|
4.1 cm x 8.4 cm
1919 - 1925
|small radiator emblem|
3.8 cm x 6.3 cm
1919 - 1929
|reverse of the small and the large emblem: no maker´s mark|