A long expression that indicates the height of the buttons, in pixels.
By default, the ButtonHeight property is 24 pixels. Use the
ButtonHeight and ButtonWidth property to
specify the height and the width of the buttons in the control. Use the PictureDown and PictureUp
properties to specify the picture for the buttons. Use the Buttons
property to customize the control's matrix of buttons. Use the LabelHeight
property to specify the height of the control's label.