Chalmers-Detroit / Chalmers

 Chalmers-Detroit (or Chalmers after 1910) were manufactured in USA from 1908 until 1924.

Chalmers Detroit (1908)
Chalmers-Detroit Motor Co.
Detroit Mich., U.S.A.

Size: 56mm x 56mm

Chalmers Motor Co. (1914-1918)
Detroit Mich., U.S.A. (R)1910

Size: 70mm x 70mm
The reverse of this emblem has a two filed-off pins, presumably a central radiator core rod and a locator pin, as well as the makers mark (a semi-circle with "Co" in centre).
Chalmers (1914-1918) (reverse)
filed-off pins & maker's mark

Size: 70mm x 70mm