Every L and U in this modular system runs through this piece: a square corner, 36 inches each way, turning a sectional through a right angle with an 18-inch seat matched to the straight units and a 25-inch overall height. Aluminum in Ash Grey, or Talc White for lighter schemes. Cushions upholster in contract textiles keyed to the adjoining modules. Fifty-five pounds. Count the corners off the floor plan first, since they define the shape everything else follows.