[This is preliminary documentation and subject to change.]
If this bit is set, the control's text is replaced by a bitmap. The text entry in the database that normally would specify the text of the control is used as a foreign key to the Binary table to point to the binary data needed for the picture. Such a control has no text associated with it. This style bit should not be set at the same time as the Icon stylebit.
0x00040000 = 262144