M3786/4-5099 is a military-qualified multi-deck rotary switch manufactured by Grayhill, designed for rugged applications requiring reliable switching across multiple circuit configurations. The switch features a 1-inch diameter with a rated current capacity of 1 ampere and is qualified to MIL-DTL-3786/4 specifications. It offers multiple deck configurations (1 to 3 decks), various angle-of-throw options (30°, 36°, 45°, 60°, and 90°), and choice of termination styles including solder lugs and PC mount options. The switch operates reliably across temperature ranges from -65°C to 125°C depending on the specific style, with 6000-cycle endurance at rated load and 1000 Vac dielectric strength. Common applications include military equipment, aerospace systems, and industrial control panels where rugged construction, long operational life, and multiple switching configurations are essential.