Sensors - Compact Automation Products Comtronic sensors are dual LED indicator for power and signal. They feature circuit protection/surge and polarity and come with or without receptacles. Compact Husky Limit Sensors are rugged design for harsh environments. They are impact resistant with LED indicator. Compact Automation Products Round Limit Sensors feature single LED indicator for signal and are low cost and compact size. Compact’s 4mm round sensors fit precisely in a compact sensor groove, for ultimate space efficiency. Other sensor products include the optional Quick Disconnect /sensor Cable and 3 Meter Socket Receptacle.