The NI 12U Series of inductive proximity sensors from Turck Banner that features Uprox.
Body Style  Cylindrical     
Primary Type  Inductive Proximity Sensors     
Series  NI12U Series     
12 MilliMeters
Length of Cable  2 Meter
Output Type  NO PNP
Number of Wires  3
Body Composition  Metallic
Operating Voltage Range  10~30 VDC