Difference between auto-recovery button and auto-lock button: 1. Self-recovery button: press this button to turn on the power (light on) Release your hand, the power will appear and turn off automatically (the light goes out) 2. Self-locking button: press the power button, release your hand, and keep the button stationary (lit) Press the button again to display and turn off the power (the light goes out). Product parameters Head type: round head Housing material: metal Operation type: Momentary self-reset or fixed self-locking Emitting color: red or yellow or blue or green or white Package:5PCS button and 5 connector bases 1.What does the signal "NC" and "NO" means "A" "and": positive pole of the led "LED" " - ": negative pole of the led " NC ": Normal Close " NO ": Normal Open " C " : Common 2.How to connect 1.Connect " NO " and " C " : The circuit is alway open unless press the button. 2.Connect " NC " and " C " : The circuit is alway close unless press the button. Press the switch, the load is energized, and the LED lights at the same time. Press the switch again, the button is reset, the load is powered off, and the LED goes out. Turn on the power, the LED lights, press the switch, and the load is energized. Press the switch again, the button is reset, and the load is powered off. Turn off the power and the LED goes out. Press the switch, the load is energized, and the LED turns off Press the switch again, the button is reset, the load is powered off, and the LED lights at the same time. Press the switch, the load is powered off, and the LED turns off at the same time. Press the switch again, the button is reset, the load is energized, and the LED lights at the same time. Turn on the power and the LED lights up. Press the switch, the load is powered off. Press the switch again, the button is reset, and the load is energized. Turn off the power and the LED goes out.