Confidential transmission of arrest orders and material required; sealed envelopes, acknowledgement slips and recordkeeping mandated. Rule 3 requires the Arresting Officer to prepare and sign an index of the order and material, include a forwarding letter, place the documents and the Form I acknowledgement slip in a sealed inner envelope marked 'Confidential' with a reference number, date of despatch, and the Adjudicating Authority's name and official seal, then place that envelope inside a sealed outer envelope with a Form II acknowledgement slip; the Arresting Officer must maintain acknowledgement slip and dak registers and record the dispatch immediately.