Description
The Intermatic K4221C is a high-quality stem and swivel-mount thermal photocontrol designed to deliver dependable, automatic dusk-to-dawn lighting control for outdoor fixtures. Built by a trusted manufacturer, this unit ensures your lights turn on at night and off at dawn — no manual intervention needed.
Key Features
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Automatic light sensing & switching — Uses a Cadmium Sulfide photocell with a mechanical bimetal switch to automatically turn lights ON at dusk (1–5 foot-candles) and OFF at dawn (3–15 fc).
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Durable, weather-resistant design — Housed in tough, UV-resistant polycarbonate with a sealed construction to withstand outdoor conditions and temperature extremes (−40 °F to 158 °F). Easy installation — Stem with standard ½"-14 NPSM threaded mount plus swivel for flexible positioning; includes washer gasket and locking nut.
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120 VAC, heavy-duty load support — Rated for up to 15 A incandescent/tungsten loads (1800 W) or 8.3 A ballast loads (100 VA), making it suitable for typical outdoor lighting fixtures.
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Delay feature for reliability — Built-in delay (30–90 seconds) helps prevent false OFF switching due to transient light sources like passing car headlights or lightning flashes.






