I have only have these dumbbell for a few short week and have not even use they that often . however , the plastic be already crack all over they !! I own other dumbbell with plastic coating and I have not have any problem with those . consider these be `` new , '' I think the quality be really poor . all dumbbell cost around the same price , so I suggest you buy another kind . I hate to see what these will look like in a few month !