49 CFR 383.21 : Transportation (§ 1.1 To Parts 1581-1699) — (Parts 300-302 To Appendix G To Subchapter B Of Chapter Iii) — Other Regulations Relating To Transportation (Continued) (Parts 300-302 To Appendix G To Subchapter B Of Chapter Iii) — Federal Motor Carrier Safety Administration, Department Of Transportation (Parts 300-302 To Appendix G To Subchapter B Of Chapter Iii) — Federal Motor Carrier Safety Regulations (§ 350.101 To Appendix G To Subchapter B Of Chapter Iii) — Commercial Driver'S License Standards; Requirements And Penalties (§ 383.1 To § 383.155) — Single License Requirement (§ 383.21 To § 383.25) — Number of drivers' licenses.