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Automann · Electrical & Lighting
178.2575
In stock · ships from Knoxville
This is an ISO mini automotive relay with four terminals (SPST – Single Pole Single Throw) rated for 12V DC and 50 amps continuous current.
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Universal fit
Universal ISO mini relay that fits standard 4‑pin ISO mini relay sockets. Used across virtually all heavy‑duty trucks, trailers, and off‑highway equipment where a 12V, 50A SPST relay is needed.
Part data verified against 5 catalog sources
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It includes a built-in resistor that suppresses voltage spikes, protecting sensitive electronics when the relay coil de‑energizes. Heavy‑duty trucks commonly use it to switch high‑current loads such as cooling fans, headlights, starter solenoids, and auxiliary lighting. You replace it when the relay fails—symptoms include intermittent operation, burned contacts, or a component that no longer powers on.
Part Number: 178.2575
RELAY ISO MINI 4 PIN 12V 50A SPST RSTR
Unit: ea
Dealer: KP Services Crossville
Compatibility, alternatives, and more
Parts commonly needed alongside electrical & lighting
