... DC voltage 440V. 1.ApplicationLAY39-22 series button switch, adapted in AC 50HZ( or 60HZ), voltage is up ... to 440V, used for control, signals, reverse function in CNC machine tools, shipbuilding, textiles, printing, electrical and ... lock level buttonMMushroom buttonZPDSelf-locking type flat button with light buttonZMSelf lock mushroom buttonMJMushroom rush buttonMJLDrawing buttonXDASignal lightSDTwo- ...