Industry standard 18 mm Dia threaded body has flat sides allowing it to be mounted like a tubular sensor or against any flat surfaceRight angle viewing models mount in a depth of only 6/10th of an inchSolid polyurethane housing completely encapsulates internal circuits for high resistance to shock and vibrationAdaptable modulation circuit provides immunity to crosstalk from other closely mounted sensorsThe industry's only background rejection sensors with a 2-wire circuit design4-wire DC sensors offer both NPN and PNP outputsOutput status indicator visible from a wide 270 deg anglePVC cable jacket, structural polyurethane foam housing, polycarbonate lensSwitch selectable light dark operationLights steady when output is on flashes when short circuit protection is in latch conditionLatching S/C protection30g over 10 Hz to 2 kHz vibration