In case you have a short hair, you must use a best hair straighteners that is at least one inch in width and for a long hair you should go for 1.5 inches wide iron. Though width of a hair straightener is necessary, it alone will not help you in straightening any kind of hair. For easily straightening any type of hair, a flat iron should have a temperature adjustment mechanism in place. Most of the  flat ironscome with adjustable dials that allow you to control the temperature of plates.