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DCC Specialties Block Watcher
This detector puts the power of a microprocessor to work analyzing the current feed to the rails. This detector has been designed to eliminate many of the installation problems associated with the installation of signal systems. The Block Watcher comes ready to install, all you have to do is to connect it between the DCC booster or circuit breaker and the rails. Then connect the detector output switch to your signal system.
Part # DCCS-bwatcher