Section 1600.20 - Types of employee contributions(a)Traditional contributions. A participant may make traditional contributions.(b)Roth contributions. A participant may make Roth contributions in addition to or in lieu of traditional contributions.(c)Contributions from tax-exempt pay. A uniformed service member who receives pay which is exempt from taxation under 26 U.S.C. 112 will have contributions deducted from such pay and made to his or her traditional or Roth balance in accordance with an election made under paragraph (a) or (b) of this section. 77 FR 26422 , May 4, 2012