Modular elements for composing frames for the construction of cabinet structures and containers for electrical, electromechanical and electronic components, for internal and external use, said elements forming the perimetral cabinet frame defined by section bars and angle pieces connected together, characterised in that the angle pieces are constituted by a corner portion from which there extend several mutually orthogonal tube portions of substantially quadrilateral cross-section;
- each of said section bars comprising a tubular element of orthogonal shape arranged for insertion onto one of said tube portions and further comprising, extending from one corner thereof in mutually orthogonal directions, two flanges from which there extend two further converging and intersecting flanges, from which intersection there extend two mutually orthogonal profiled portions being provided with means arranged for supporting electronic and electromechanical containers.