It is 22 mm non-metallic pushbuttons are heavy duty industrial control devices available with a wide range of Illuminated and Non-Illuminated Operators. The buttons are fully gasketed for Type 4X (IP65) protection. This is to prevent the entrance of water, oil, and dirt past the operator into the enclosure. The modular construction makes on the job assembly both fast and simple. The contact blocks are stackable up to a maximum of 4 contact blocks allowing many combinations of control layouts.