var imageFiles_50_55 = new Array();
imageFiles_50_55['0'] = new Array ('_images/50_Product_Catalog.gif', '_images/50_Product_CatalogMouseover.gif');

function image_on_50_55 (position) {
   var doc = eval("document.image50_55" + position);
   doc.src = imageFiles_50_55[position][1];
}

function image_off_50_55 (position) {
   var doc = eval("document.image50_55" + position);
   doc.src = imageFiles_50_55[position][0];
}