The 12166A is a four-pole professional toggle switch from the 12000 series, designed for high-specification environments requiring robust switching performance. It features solder lug terminals with a 26° angle of throw and ON-OFF-ON switching function across all four poles, with a threaded bushing of Ø 11.9 mm (15/32-32UNS) for secure panel mounting. The switch is CECC approved and conforms to military specifications, offering smooth mechanical toggle action and multiple front panel sealing options for protection against dust and water. Key electrical characteristics include a maximum current rating of 4 A at 30 VDC with silver contacts, initial contact resistance of 10 mO maximum, and insulation resistance of 1,000 MO minimum at 500 VDC. The 12166A is ideal for aerospace, defense, industrial control, and other demanding applications where reliability and precise switching control are essential.