Crouse-Hinds series 4" steel octagon concrete boxes are used in poured deck applications that are common in high rises, apartments, condominiums and restaurants with outdoor dining areas. The boxes are installed on wooden or steel forms and concrete is poured. Upon removal of the forms, the box is flush with the concrete. Additionally, the TP643 within this concrete box family is fan rated. Because of the additional mounting support boss and locknuts, this new box is suitable for use with fans of up to 70 pounds and fixtures up to 90 pounds.