ITEM NAME:Inductive Proximity Sensor SN04-N DC NPN NC 4MM DC 6-36V Proximity Switch #gib Store Home Promotion Hot Item Add to Fav.Output: NPN DC Tri-Line NC. Detection Type: Inductive. Response Frequency: DC : 0.5KHZ AC:25HZ. 1 X Switch. Add to Fav. If item is defective after 3 months, you can still send it back to us. We will send you a new one after receiving the defective item.