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Brown 4-pin relay harness with wiring, model 821

Vszerda

Vszerda 821 12V 24V 40A 4pin Relay Harness

SKU CH-MXY3-27B71

A 40 A relay harness switches 12 V or 24 V circuits for air conditioning, HID fog lights or headlights using a four-pin brown housing

  • Ready for 12 V and 24 V systems
  • Handles up to 40 A continuous load
  • Standard four-pin layout simplifies wiring
  • Brown housing identifies the 821 model

Automotive Relay Harness for Lighting and Climate

The Vszerda 821 wiring harness integrates a 12V or 24V 40A four-pin relay with a brown back shell. It is designed for car air-conditioning circuits, HID fog lights and headlight installations. The pre-wired assembly suits DIY installers and professional auto-electricians who need a ready-to-fit switching solution.

Sustained 40 Amp Switching Without Derating

The relay contacts are rated for continuous 40A operation at both 12V and 24V, so the harness maintains full current capacity during extended compressor or lighting cycles. Heat buildup in the sealed housing stays within design limits for prolonged use. Installers who require higher amperage or a different pin layout will need a separate harness.

Highlights

  • Ready for 12 V and 24 V systems
  • Handles up to 40 A continuous load
  • Standard four-pin layout simplifies wiring
  • Brown housing identifies the 821 model

Specifications

No published specifications for this item yet.

Questions about this item

How much heat does the 40A relay generate during continuous operation?

The 40A relay is designed for standard automotive duty cycles; prolonged continuous load may increase temperature, so ensure adequate airflow around the brown back shell.

What existing vehicle wiring is required to install this 4-pin harness?

You need a 12V or 24V power source, a switched trigger circuit, and a load such as HID fog lights or an air-conditioning compressor compatible with the 4-pin layout.

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