function changezone(zone){
	zone_array = new Array("DESCRIPTION","SPECIFICATIONS","GEOMETRY");
    for(i=0;i<3;i++){
		if(zone_array[i]==zone){
		    document.getElementById(zone_array[i]).style.display="block";
			document.getElementById("tag_"+zone_array[i]).className = "on";
		}else{
		    document.getElementById(zone_array[i]).style.display="none";
			document.getElementById("tag_"+zone_array[i]).className = "off";
		}
    }
}