6V

6V or 6-V may refer to:


 * 6V, IATA code for Mars RK airlines
 * 6v, abbreviations for 6 volts
 * 6V, abbreviation for 6-valve engine
 * 6V-71, engine used in Detroit Diesel Series 71
 * 6V-92, engine used in Detroit Diesel Series 92
 * 6V, the production code for the 1985 Doctor Who serial Vengeance on Varos