The Product have Customized high quality connection， using 22AWG wire， copper wire inside is very thick， can be resistant to current 2A， 300V voltage. An insulating layer over a wide range of temperatures， up to 80 degrees. Not easy to break， easy to use. Red line connecting VCC (ramps of +)Connect the black wire GND (ramps of -)Green Line connection SIGNAL (ramps in s) Package Contents - Mechanical Limit Endstop Switch 3D Printer x 3