Letter of Undertaking for export without integrated tax: procedural acceptance and bank guarantee guidance for exporters. Registered persons exporting without integrated tax must furnish a bond or Letter of Undertaking in FORM GST RFD-11 prior to export; until the portal is operational the bond/LUT and FORM GST RFD-11 shall be submitted manually to the jurisdictional Deputy/Assistant Commissioner over the exporter's principal place of business, with the exporter able to present before Central or State tax authority, and the Joint Commissioner empowered to determine any bank guarantee amount, which should normally not exceed 15% of the bond, while maintaining office records and prescribed registers.