1. PAN Card of Applicant (Remitter)
2. Invoice for which payment is to be made.
3. No PE Declaration from Non Resident ( if applicable)
4. Bank Account Details (Cancelled Cheque) from which payment is to be made
5. BSR Code ( Branch code of bank from which payment is to be made.
6. Digital Signature of Remitter..
15CA is a mechanism to collect information by Income Tax Department for payments made abroad.
15CB is a certification by Chartered Accountant for authenticity of data filled and to prevent evasion of Tax..