Op-Art pioneer Victor Vasarely was profoundly influenced by Bauhaus, constructivism, cubism and surrealism. He began his unmistakable geometric abstraction from the 1930's through his heyday of optical illusion of the sixties and seventies. Late in his career, Bulova produced a series of wristwatches with Vasarely's artwork on the dial and engraved signature on the caseback. Very difficult to find, one of the more interesting models was the "Four Squares" (pictured above). A double-sided propeller-style seconds hand made this watch even more unique.