Probable one of the most popular French St.Christopher dashboard badge. This same piece could be ordered on the 1920s and 1930s in different sizes and with enamel finish on borders decorating the prayer.
Diameter 30mm. Silver plated bronze. Unsigned but marked OBC.
Similar example photographed and described in Maximiliano Garay’s book ” Saint Christophe – dashboard badges of the golden era of motoring ” on page 195.