The optical switch is a reliable stop/switch solution for any type of 3D printer/CNC/3D tool. Advantages: Compared to mechanical switches, this is smaller and more compact Repeat positioning is in high accuracy., no mechanical collision Triggering is sensitive and quiet Using optically transmissive principles of design, no loss, no noise, and longer life(more than one hundred thousand times).Tips: Generally, the system needs at least three optical switches.Specifications: Color: Black Cable type: 3pin XH2.54 supporting switch cable Cable length: 1M For: 3D Printer Size: refer to the product picture