4 mm NPN-常闭 块状 电感接近传感器, M12, 15 mA, 12 → 24 V 直流, IP68, IP68g
电感 接近 0.13"（3.3mm） IP68 模块
得捷:
SENSOR PROX INDUCTIVE 3.3MM MOD
Allied Electronics:
Sensor, Proximity, Inductive, M12, 4mm Range, 3 Wire, NPN, NC, 1 Meter Cable
Newark:
Inductive Proximity Sensor, Rectangular, GX-H Series, Stable, 4 mm, NPN, 12 to 24 V, Pre-Wired