jQuery.extend({
  UnitUtil: (function() {
    var pxWidth = 0;
    var tmpNode = document.createElement("DIV");
    tmpNode.style.cssText =
      "width:1mm;position:absolute;left:0px;top:0px;z-index:99;visibility:hidden";
    document.body.appendChild(tmpNode);
    pxWidth = tmpNode.getBoundingClientRect().width;
    tmpNode.parentNode.removeChild(tmpNode);
    
    return {
      mm2px: function (mm) {
        return parseFloat((mm * pxWidth).toFixed(0));
      },
      px2mm: function (px) {
        return parseFloat((px / pxWidth).toFixed(0));
      }
    };
  })()
});