The System Sensor B504AP is an analogue sensor base with SEMS screw connections for isolated and non-isolated detectors and address identification label.
 
The B501AP Base is designed to accept S200 detectors and has a tamper resistant feature which can be enabled by breaking off a plastic tab. When enabled the detector cannot be removed without a suitable tool. The base can be labelled with a break-off address tag. Available in white, ivory and black colours.