47 CFR § 87.87 - Classification of operator licenses and endorsements.
(a) Commercial radio operator licenses issued by the Commission are classified in accordance with the Radio Regulations of the International Telecommunication Union.
(b) The following licenses are issued by the Commission. International classification, if different from the license name, is given in parentheses. The licenses and their alphanumeric designator are listed in descending order.
(1) T-1. First Class Radiotelegraph Operator's Certificate. Beginning May 20, 2013, no applications for new First Class Radiotelegraph Operator's Certificates will be accepted for filing.
(2) T-2. Second Class Radiotelegraph Operator's Certificate. Beginning May 20, 2013, no applications for new Second Class Radiotelegraph Operator's Certificates will be accepted for filing.
(3) T-3. Third Class Radiotelegraph Operator's Certificate (radiotelegraph operator's special certificate). Beginning May 20, 2013, no applications for new Third Class Radiotelegraph Operator's Certificates will be accepted for filing.
(4) T. Radiotelegraph Operator License.
(5) G General Radiotelephone Operator Licenes (radiotelephone operator's general certificate)
(6) MP Marine Radio Operator Permit (radiotelephone operator's restricted certificate)
(7) RP Restricted Radiotelephone Operator Permit (radiotelephone operator's restricted certificate)