an integrated clock an additional button or buttons could be added to support the additional clock function s another example might include an alarm function which causes an audible alert or a vibration if a predetermined exposure level has been exceeded fig4 shows the top view of the wristband according to an exemplary embodiment and shows that a display unit may be composed of any number of light emitting diodes led s 4 arranged in a circular manner in order to minimize footprint the led s 4 not only display the real time uva b dose in an adaptive way but may also serve as indications for ss setting and uvi indication when the appropriate selection buttons are depressed of course the led s may be arranged in patterns other than a circular one for example the led s might be arranged in a line a semi circle a rectangle a diamond etc it should be noted that exemplary embodiments could employ displays indicators other than led s for example a liquid crystal display lcd or an e ink display might be used to display the adaptive real time uva b dose and or indications for skin sensitivity ss and uvi when the appropriate selection buttons are depressed further the display unit could be.