Remove text from text input when get focus

<input type='text' style='margin:0 10px;background-color:#F3FAAA;width:250px;height:16px;vertical-align: text-bottom;;' name='search_text' id='search_field' value='Ex.: Dell Latitude D620 enter D620 only' onfocus='$(this).val(\"\").css(\"color\", \"#000000\")' 
	onblur='($(this).val() == \"\") ? $(this).val(\"Ex.: Dell Latitude D620 enter D620 only\").css(\"color\", \"#9B9B9B\") :  $(this)' />