System Sensor B300-6-BPThe Mounting Base is required to meet local code and application requirements and for that System Sensor offers standard 4in and 6in bases, as well as, specialty base designs including relay, isolator, sounder and low frequency sounder options for Select Series detectors. The standard 4" and 6" bases offer a plug in detector base intended for use in intelligent systems, with screw terminals provided for power (+ and ), and remote annunciator