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  image1subon.src = "../images/airduct/airducton_home.jpg";

  image2subon = new Image();
  image2subon.src = "../images/airduct/airducton_tenstep.jpg";

  image3subon = new Image();
  image3subon.src = "../images/airduct/airducton_didyouknow.jpg";

  image4subon = new Image();
  image4subon.src = "../images/airduct/airducton_recommendations.jpg";

  image1suboff = new Image();
  image1suboff.src = "../images/airduct/airduct_home.jpg";

  image2suboff = new Image();
  image2suboff.src = "../images/airduct/airduct_tenstep.jpg";

  image3suboff = new Image();
  image3suboff.src = "../images/airduct/airduct_didyouknow.jpg";

  image4suboff = new Image();
  image4suboff.src = "../images/airduct/airduct_recommendations.jpg";

}

function changeImages() {
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}