The optical endstop is a reliable limit swtich/ endstop/ switch solution for any type machines such as 3D Printer, CNC, Robot, Drawing bot etc. It supports RAMPS, MKS Tiny Bee, Robin, CNC shield etc. boards. It's designed with the principle of optical transmission which is a contact-less, loss-less, noise free solution. It provides long service life, reaching more than 100,000 times.