Grindable formwork body for direct and seamless installation of round, levelable cassettes, nominal size R9, in surface-finished screeds / terrazzo floors. The formwork is placed floating on underfloor boxes with mounting cover nominal size R9 and closes the gaps between the underfloor box and the cassette frame. The protective cover made of aluminum sheet is inserted into the cassette frame as a dummy before the screed work and can be sanded over with the screed/terrazzo.
