The system is realized with standardized systems that foresee the motorization and its protection in a special Grinzi de aluminiu structure (see the page devoted to 5P - Policinale screens, that represents the modern evolution of the ancient revolving bar curtain).
Variations
the dimensiune (standard lăţime from 8 m to 12 m, but the realization cu superior lăţime, up to 20 m or beyond, is not infrequent)
the position of the engine (central or side)
the compoziţie of the cortina or the ecran (tulle, folie pentru proiecție faţă, folie pentru retroproiecție, etc.)