The SEZ units may import and export through port, airport, land custom stations, ICD ,CFS courier mode (other than valuables ) and post parcel. The software development units may import and export through data communication and telecommunication links. So far as exports through data communication and telecommunication links are concerned, the procedure and practice being followed in case of SEZ/STP units may be adopted font SEZ units. As for import of software through above modes, the units may be asked to file the Bill of Entry within 24 hours of such imports along with bank attested invoice and other relevant documents for obtaining national "out of charge ". The documents such as invoice etc. in respect of such import shall be routed through banks. The director or the STP/development Commissioner of SEZ shall certify the value of such software. Further, in case of such software imports, instructions issued by RBI, if any, may be followed.