2 pcs Inductive Proximity Switch: 1 pcs LJ18A3-8-Z/BX 8mm & 1 pcs LJ12A3-4-Z/BY 4mm   It is a component widely used in automatic control industry for detecting, controlling, and noncontact switching.   When proximity switch is close to some target object, it will send out control signal.   It's widely used in machine, paper making, light industry for limiting station, orientation taking count, speeding trial ect.   Metal shell, DC type, 4mm detecting distance, 3 wire system.Power supply inverted connecting protection, short circuit protection, non-contact detecting device.      Product Name: Inductive Proximity Switch;   Theory: Inductive Type Sensor   Model: LJ18A3-8-Z/BX & LJ12A3-4-Z/BY   Switch Appearance Type: Cylinder Type   Wire Type: DC 3 Wire Type (Black, Brown, Blue);   Output Type: PNP, NO;   Detect Object: Iron   Current Output: 300mA;   Supply Voltage: DC 6-36V;   External Material: Plastic, Metal   Color: picture color   Diameter of Head: 18mm / 12mm   Detecting Distance: 8mm/ 4mm   Cable Length: 1.1M/43.3 inch      Package Content:   2 x Inductive Proximity Switch      Only the above package content, other products are not included.   Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.