A tensioner for a seat belt includes a cylinder tube, a piston that is movably arranged in the cylinder tube, a tension transmission means connected to the piston at a connecting portion for transmitting the movement of the piston to the seat belt, as well as a drive which is adapted to exert a driving force in a tensioning direction A on the piston so as to tension the seat belt. A mobile information terminal acquires a right to execute content. The fuel plates are composed of elementary fissile particles, preferably uncoated, embedded in a metallic matrix.