a device and method are disclosed for the production of hollow bodies , especially plastic bottles , wherein a section of a plastic flexible hose is placed in a cavity of a blow mould by an extruder head according to a predefined clocked pulse . the plastic flexible hose is inflated inside the blow mould by a blow mandrel by overpressure according to the blow mould cavity . the manufactured inflated hollow body is subsequently removed from the mould . the plastic hose can be continually held on opposite sides of the blow mould arrangement during the entire extrusion and blow cycle .