Invoice requirements for CENVAT compliance: format, mandatory registration details, pre authentication exception for computer invoices. The notification prescribes required invoice particulars and format for CENVAT compliance, including colour coded copies, requirement that first and last invoice book copies be pre authenticated (except computer generated invoices), and that invoices be pre printed with issuer name, address, Central Excise registration number, Range/Division/Commissionerate and tax registration numbers. The Annexure sets a proforma listing issuer, consignee, supplier and manufacturer/importer details, goods description, identification marks, quantity, value, duty rate and amount, transport and timing details, and a certificate concerning source or receipt of goods, with limited particulars permitted to be filled later if initially unknown.