Inductive Proximity Sensor, E51 Series, Head, Side SensingInductive Proximity Sensor Head, E51, Side Sensing, Shielded, . 51" Sensing Range, Standard Frequency, Programmable NO or NC operation. Used to detect Metallic objects. Standard E51 sensors feature long sensing ranges and a choice of top or side sensing heads. Alternate frequency units eliminate interference when mounted close to standard frequency units. Order sensors in component form, as assembled plug in units, or in a sealed version where the