This BNC manual data switch box can be used to switch between four coaxial BNC devices for use with one coaxial BNC display or one BNC device to four BNC displays. Connectors are fully shielded for maximum EMI/RFI protection. Heavy-duty dial contorl switch knob. Anti-skid rubber feet. BNC connectors. BNC I/O female x 1 + ABCD port female. Switch box does not require power. Cable may be required sold seperately. Standards: UL, CSA, ISO 9001:2000 manufacturer.