Use SCT to export certificates and private keys to the local file system. Exporting certificates is an optional precautionary measure that allows you to export and store certificates to a computer or removable media for safekeeping. Keep in mind that certificates with private keys are sensitive information that you should treat as highly confidential files.
Three file formats are supported: *.pem, *.cer, and *.crt. Typically, each device has two or three certificate files to export: one root, one intermediate, and one server certificate. Some devices may have more than one intermediate certificate. Whatever the case, always export every certificate file that the customer's IT department or CA provides from the CSR you sent them.