This is a 1921 American Red Cross, Financial Development (fundraising), tin stick pin.  It is 9/16" in diameter and is intact.  The pin is white with a red cross in the center.  "1921" (in blue) is below the cross.  The manufacturer information on the back side of the pin reads "J.L. Lynch, Chicago Ill". There is wear to the front side of the pin, mostly small white spots showing through the red cross, so it was obviously well used.  The stick pin on the back is intact.

This pin was listed as being produced in 1917 (?) with the 1921 date.  I am just going with 1921 as the production date, but the pin was probably manufactured before that year so it could be used for the 1921 fundraising drive.