Amazon.com: Telemecanique XS Universal Series Inductive Proximity Sensor, Multi-Function, Plastic 117 x 40 x 40 mm Rectangular Body, 3-Wire DC PNP, PNP Input, NO/NC Output, Screw Term. w/ 1/2" NPT Cable Entry :
SENSOPART FT 25-R-PS-M4M IP69K Enclosure Rating, Proximity Sensor, 800 MM MAX Working Distance, PHOTOELECTRIC, Teach-in Adjustment, M8-4 PIN Metal Plug, PNP-Normally Open Output: Amazon.com: Industrial & Scientific
TRI-TRONICS EZPRC DIN Rail, RED LED, 45 MA, NPN/PNP Output, Light EMITTER, M12 Connector, Sensing Range Depends ON Optical Block, PHOTOELECTRIC Sensor, SMARTEYE EZ-PRO, 5-Wire, Polarity Protected, 1: Amazon.com: Industrial & Scientific
Omron D5A-3210 High Precision Switch, Solid State PNP Output, Operation Indicator, Prewired, Pin Plunger, M8 Body Type, IP67 Protection, 1um max Repeat Accuracy, 0.49N Max Operating Force, 1m Cable Length: Electronic Component