- SBC-2 installation instructions for the conventional sounder base 12/24V 2 wire. - SBC-2R installation instructions for the conventional sounder base, role, 12/24V 2 wire. - SBC-4 installation instructions for the conventional 4 wire sounder base. FEATURES: - Wide operating voltage - Selectable Evacuation Codes: Continuous orTemporal - Three different configurations: individual, group, and global modes - High sound pressure level (85 dB at 10 ft) - Can be configured to satisfy a wide variety of applications - Available with or without relay, 2 and 4 wire configurations, and Bone or White color.