Mountable on transparent piping with an outer diameter of 6 to 26 mm and a wall thickness of 1 to 3 mm for detecting the upper level of the internal water surface. Offers heat resistance up to 100°C. Equipped with a mounting position adjusting lever for easy installation. In this paper, a novel liquid level sensing system is proposed to enhance the capacity of the sensing system, as well as reduce the cost and increase the sensing accuracy. The “Plug & Forget”. FU-95Z, Liquid-level-detection Fiber Unit in FS-N40 series by KEYENCE America. A liquid accumulation prevention structure is used for all liquid level contact type models.