These sensors work electronically like any other photoelectric sensor, with the difference that the light emitted and received is transported by a fiber optic, which has a very small and variably shaped end and can be installed at a distance from the electronic measurement circuit or amplifier, made in stainless steel cylindrical housing AISI 303 M18X1 with fixing brackets. Different models are available according to the type of application. They can be 2 mt. standard and are covered by polyethylene and have either a smooth metallic end of 3mm. dia. or threaded M4-M5-M6.