H8000 type boxes feature wide flanges that provide ample contact with cover and gasket to insure tightness even under widely varying temperature and climatic changes. Flange widths are graduated from a minimum of three quarters of an inch on small boxes to a width of one and a half inches on large boxes. Screws are properly spaced to make these boxes weathertight under severe natural forces of driving rain, snow, sleet or drippage.