Neptune Systems – Optical Level Sensor with Magnetic MountThis Neptune Systems OS-1-M Optical Level sensor w/ Magnetic Mount plugs into yourNeptune Systems FMMand, using reflected infrared light, will signal your Apex when it changes state from being wet to dry or dry to wet. This sensor can be used for constructing your own ATO (auto-top-off), as a high-level warning sensor in your sump, water storage level sensor, and much more. The sensors can be mounted on any type of reservoir that has up to 1/4″ thick walls.Neptune Systems – Optical Level Sensor with Magnetic MountThis Neptune Systems OS-1-M Optical Level sensor w/ Magnetic Mount plugs into yourNeptune Systems FMMand, using reflected infrared light, will signal your Apex when it changes state from being wet to dry or dry to wet. This sensor can be used for constructing your own ATO (auto-top-off), as a high-level warning sensor in your sump, water storage level sensor, and much more. The sensors can be mounted on any type of reservoir that has up to 1/4″ thick walls.Compatible withNeptune Systems FMM ModuleMagnet mounts to walls up to 1/4″ thickCan be mounted vertical or horizontalIncludes: 1x OS-1 Optical Sensor with nut and washer and 1x OS-M Optical Sensor Magnetic MouProduct code: 6495Item No. CT-NS-OS-1-M