obr1out = new Image; 
obr1out.src = 'images/konstrukce-detaily/konstrukce-detaily_01.jpg';

obr1over = new Image; 
obr1over.src = 'images/konstrukce-detaily/konstrukce-detaily-on_01.jpg';


obr2out = new Image; 
obr2out.src = 'images/konstrukce-detaily/konstrukce-detaily_02.jpg';

obr2over = new Image; 
obr2over.src = 'images/konstrukce-detaily/konstrukce-detaily-on_02.jpg';

obr3out = new Image; 
obr3out.src = 'images/konstrukce-detaily/konstrukce-detaily_03.jpg';

obr3over = new Image; 
obr3over.src = 'images/konstrukce-detaily/konstrukce-detaily-on_03.jpg';

obr4out = new Image; 
obr4out.src = 'images/konstrukce-detaily/konstrukce-detaily_04.jpg';

obr4over = new Image; 
obr4over.src = 'images/konstrukce-detaily/konstrukce-detaily-on_04.jpg';


function over(num) 
{
  eval("obr"+num+".src=obr"+num+"over.src;");
}
function out(num) 
{
   eval("obr" +num +".src=obr"+num+"out.src;");
}