Atlas Sound MO-2 Compact Mobile Communication Loudspeaker - U.S.-Made Compression Driver Assures High Reliability. - Heavy-Duty Loudspeaker with Optimum Voice and Signal Intelligibility for Industrial, Marine, Military and Vehicular Applications. - Specifically Designed for Surface or Concealed Mounting. - Impact and Environment-Resistant Construction for Dependable Indoor/Outdoor Use. -Ideal for concealed mounting or where minimum aerodynamic obstruction is desired.