var arrayprodcats = new Array();

  function toggletab( tabclicked ) {

    for (tab = 1; tab < arrayprodcats.length; tab++) {
      document.getElementById('tab_' + arrayprodcats[tab]).className = 'tab';
      document.getElementById('box_products_' + arrayprodcats[tab]).className = 'box_products_holder';
    }

    document.getElementById('tab_' + tabclicked).className = 'tab tab_active';
    document.getElementById('box_products_' + tabclicked).className = 'box_products_holder box_products_holder_active';

  }