RN is an identity document (ID) of the .lt domain. The domain holder’s ID (RN number) is required when a registrant of the .lt domain wants to transfer to another registrar or performs the procedure of domain trade (transfer of the registrant).
The .lt domain holder’s ID is identified on your account; choose the menu item “Initiate domain trade” or “Initiate transfer of the registrar”).
.lt domains do not have the authorisation codes that are present in the .eu, .com., info, .net or .org domains.
More information on the transfer of the registrar in the .lt domain is available here: https://www.domreg.lt/en/faq/for-domain-registrants/how-to-transfer-servicing-registrar/
More information on the domain trade in .lt domain is available here: https://www.domreg.lt/en/faq/for-domain-registrants/how-to-trade-your-rights-to-domain-to-another-person/