function loadTour(Month, Value, dropdownId)
{
    if (Value != 0)
    {
        switch(Month)
        {
            case 'Apr':
            window.location.href = "/shop/product.php?productid=581&po_id="+dropdownId+"&selected_date="+Value;     //581
		    break;

            case 'May':
            window.location.href = "/shop/product.php?productid=582&po_id="+dropdownId+"&selected_date="+Value;
		    break;
    	}
    }

    else
    {
         alert('Please select a tour date.');
    }
}