if (document.images) {
 var img0 = new Image(); img0.src="image/top_50th.jpg";
 var img01 = new Image(); img01.src="image/top_LEGAdvantageLine.jpg";
 var img02 = new Image(); img02.src ="image/top_OB25XT.jpg"; 
 var img03 = new Image(); img03.src = "image/top_IMPComfortS.jpg"; 
 var img04 = new Image(); img04.src = "image/top_STELLALLtd.jpg"; 
 var img05 = new Image(); img05.src = "image/top_STELLARLtd.jpg"; 
 var img06 = new Image(); img06.src = "image/top_REVESTAS.jpg"; 
}

function On(name) {
 if (document.images) {
  document.images['def'].src = eval('img' + name + '.src');
 }
}

function Off(name) {
 if (document.images) {
  document.images['def'].src=img0.src;
 }
}