DHF contains records necessary demonstrate that the design was developed in accordance with the approved design plan and requirement of the FDA’s design control.DHF contains detailed design plan,design input,design output,risk analysis,design verification and design validation and design transfer.Technical file describe the product at a point in time includes some elements of DHF like risk management documents and clinical data .TF addresses that product is MDD class I and class IIa or IIb while design dossier addresses product is classIII.DHF is more detailed than technical file,it is more useful.Newer EU regulatory guidance documents are moving TF/DD more in the direction of DHF