Safety apparatus

The invention relates to a safety apparatus, in particular for motor vehicles, having a safety belt, a spool movable between a blocked position and a released position for the winding up and unwinding of the belt, and a pretensioner which is drivably connected to the spool in the winding up direction, wherein the pretensioner has a drive arrangement by which the spool can be set rotating at two engagement positions spaced apart along the spool axis.