The earliest followers of Jesus were persecuted and forced to worship in hidden locations.  Often these believers would scratch the secret symbol of a fish in the ground to help them identify other Christians. 

Not only was fish a common food of the day, often used and referenced by Jesus during His ministry, but the letters which make up the Greek word for "fish" (IXOYE) also spell out a secret message about our Lord: I - "Jesus", X - "Christ", O - "God's", Y - "Son", E - "Savior".  The fish symbol transcends differences in cultures and denominations.  Throughout generations the fish symbol continues to identify the true followers of Jesus Christ.

This fish with cross auto emblem has a guaranteed weatherproof finish and attaches to a flat surface with its permanent adhesive backing.  Measures about 5" x 1 3/4".