A wide variety, normally open type / normally closed type, as well as, different frequency type, etc., is available. Two Panasonic GL compact & low price inductive proximity sensors can be mounted close together because different frequency type are available. The GL-18HL type can be mounted with a space of 20 mm 0.787 in between the two sensors. GL-18HL type offers a long sensing range of 12 mm 0.472 in. Small variations in the positions of the sensing objects do not affect detection. GL-18H/18HL type are resistant to oil and have a protection structure IP67G. The GL series incorporates an operation indicator ( GL-18H/18HL type: red) for operation check. The GL series satisfies the need for a low price inductive proximity sensor. It is recommended to large volume users for cost reduction.