Martini Gradnja in its manufacturing subsidiary has roof beam with double slope of 6% and 10%. Beam has a variable cross-section and is made of prestressed concrete, while in the end is characterized by a full rectangular section. A roof beams are manufactured in two sizes/widths 50cm I 54cm. They rely on neoprene, while thay whitstand secondary RC element such as purlines or beams and TT slabs. The beam has openings on the endings that are set on the reinforcing bars that are outside the pillars. Openings are later filled with cement mortar. Types, dimentions and carrying capacity are presented in following tables and diagrams at the pdf specification.