Joint system for structural floor joints in seismic areas, up to 300 mm in width, subject to movements up to +/- 60 mm, in commercial and industrial environments, also subject to heavy traffic of forklifts and transpallets. The system, with a rectangular section without side sub-flooring flaps and visible screws, is made up of a rigid central trolley in visible non-slip knurled aluminum and double side rubber gasket with high resistance to vertical loads. The particularly low height allows it to be placed on the same laying surface as the adjacent flooring.