They are important but know this. Those little cheap ones, you get what you pay for. If there is a little serge (which you may never know) it stops what little protection they offer but the light still works but at that point, all they are good for is an extension cord. Buy a good one, when you look at the price just remember how much you spent and how much replacement cost would be for a new machine. It'd be cheaper for me to replace laptop than my machines