The 8166K23 is a self-locking rocker switch designed for safety applications with a single pole-single throw configuration and on-off operating function. It features a 20A contact rating with silver contact plating, a red rocker actuator with glossy finish, and white on-off indicator markings. The switch is panel-mounted vertically with a 21.08mm x 36.83mm (0.830 in. x 1.450 in.) panel cutout, quick connect termination, and a 6.35mm (0.250 in.) terminal tab width. It is UL recognized (File No. E46765) and CSA certified (File No. LR164196), with RoHS and ELV compliance. This switch is ideal for industrial control panels, machinery safety systems, and applications requiring reliable on-off switching with locking functionality.