The INOmax DS IR delivery system, is not compatible with the upgraded version of the Leoni plus ventilator, manufactured by Lowenstein Medical. the Leoni plus ventilator was recently upgraded by Lowenstein Medical, with new hardware and software, and the upgraded version cannot be appropriately connected with the INOmax DS IR as instructed in the INOmax DS IR operators manual (om). the INOmax DS IR om requires warns that the one-way valve must be used. Recall start date: June 29, 2022