(Block Occupancy Detector-4)  This board operates as a DCC occupancy detector for 4 blocks using remote CT coils. It outputs logic levels, and has a RR-CirKits standard ribbon connector interface. The "Power-Lok" feature optionally monitors the DCC bus power. A power failure latches the detection status of each block until power is restored and re-stabilized. There are also 4 general purpose I/O connections fed through to the driver board.

The CP version also includes dual turnout drivers. When used with the Tower LCC or Signal LCC boards there are also 4 general purpose I/O connections. These are not available when used with older LocoNet based devices.