Underfloor device box with mounting cover and cover blanking plate with side walls made of sheet steel. For the installation of a square device insert GES9 55 in screed heights from 55 mm. Can be continuously leveled to the nominal screed height and the screed can be worked flush with the screed edge. With pipe entry openings on each side 7 x M20, 3 x M25, 4 x M32. Usable pipe size with a system height of 55 mm: M20.