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Nilight Electric Fuel Pump Relay Kit Wiring Harness 10 Gauge Cables | w/40 AMP Relay Heavy Duty 30 AMP Blade Fuse 12V System for Trucks Cars RVs Marine Boats Trailers

  • Based on 65 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Thursday, Aug 13
Order within 14 hours and 17 minutes
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Size: Fuel Pump Relay Kit


Features

  • Wide Application:The electric fuel pump relay kit is 40 Amp and universal for 12V ststem. Relay is 40A,Fuse is 30A. Fit for any device with 12V activation but no more than 40 amperes.
  • Easy to install:All wires are color-coded. And an easy-to-follow wiring diagram is included in the package. 10 feet 10 meter red wire to +12V battery, 6 feet 10 meter orange wire to fuel pump, 2 feet 16 meter brown wire to 12V trigger switch, 4 feet 16 meter black wire to chassis ground. Just plug and play.
  • Heavy Duty Long Wires:Electric fuel pump wiring harness relay kits are manufactured with high quality materials and advanced processes for high reliability and stability. With heavy duty long wire, it is easy to connect the pump directly to the battery, ensuring that the high pressure fuel pump gets the required voltage. Keep the fuel pump pressure constant to prevent the voltage drop of the fuel pump and the overload of the fuel pump current from damaging the vehicle electrical system.
  • Waterproof:40 Amp Heavy duty relay and inline waterproof fuse box. The heavy duty design make it safe and durable so it can work in any harsh conditions.
  • Package Includes : 1 x relay base with harness, 1 x 40 amp heavy duty relay, 1 x in-line waterproof fuse holder, 1 x 30 Amp fuse, 3 x heat shrink ring terminals, 2 x wire connectors, 1 x wiring diagram.

Description

About Us With over 7 years of experience in the wiring harness field, Nilight produces products that are long-lasting, powerful, and simple to use. Nilight produces quality products with cost-effective offers. With rich industry experience and advanced technology, Nilight combines industry-leading research and knowledge to build innovative wiring harnesses that are at the forefront of design, intelligence, and power. Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Visit the Store Specially designed cap for tight sealing, efficiently prevent water and dust from entering, upgrading waterproof performance. The relay is high quality made with well conductive pins. It effectively protects the circuit and the lighting system. Our wire made of high-quality tinned copper-more flexibility, hight conductivity,low resistance and anti-oxidation,anti-aging,anti-corrosion. Strip the wire insulation, crimp the terminal barrel and crimp the wire, and use a heat gun to heat it for a safe, long-lasting connection in seconds. Heat Shrink Terminal Crimp Connectors 30/40A 12V SPDT Relay 30/40 Amp Relay Fuse Holder 5 Pin Rocker Switch Standard Fuse

Connector Type: Plug-In


Contact Material: Copper


Contact Type: Normally Open


Current Rating: 40 A


Mounting Type: Surface Mount


Connector Type: Plug-In


Contact Type: Normally Open


Current Rating: 40 A


Mounting Type: Surface Mount


Operation Mode: Automatic


Wattage: 450 watts


Coil Voltage: 12 volts


Contact Current Rating: 40 A


Maximum Switching Current: 40 A


Maximum Switching Voltage: 12 volts


Minimum Switching Voltage: 12 volts_of_direct_current


Specification Met: CE


Brand Name: Nilight


UPC: 840323918909


Unit Count: 1 Count


Included Components: Fuel Pump Relay Kit with Installation Accessories


Manufacturer: Nilight


Model: 50225A


Part Number: 50225A


Contact Material: Copper


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Aug 13

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

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Top Amazon Reviews


  • Great product, simplistic and effective!
Size: Fuel Pump Relay Kit
I didn't use the connectors it came with, but the quality of the wire and the thickness was far superior to what I had. I'm running 3 wahlbro 525s in my project car with these relays. Everything's been running great, I have no complaints. Additionally, wires were super super long which was awesome for less splicing. ... show more
Reviewed in the United States on June 16, 2026 by Joe

  • Great price and great item.
Size: Fuel Pump Relay Kit
Works great. Fixed all of my fuel pump voltage dropping issues.
Reviewed in the United States on June 28, 2026 by Mitt

  • Perfect kit
Size: Fuel Pump Relay Kit
Solid build and gives you exactly what you'll need.
Reviewed in the United States on May 18, 2026 by Bo

  • Easy to install
Size: Fuel Pump Relay Kit
Been wanting to hardwire my fuel pump for many years now and this kit made it very easy to do! This took all the guess work out of the equation. I always purchase Nilight products the quality is always great for the pricing.
Reviewed in the United States on March 30, 2026 by Juanito Cheeto

  • Good
Size: Fuel Pump Relay Kit
I used to power a light bar and went to a 20 amp fuse works great
Reviewed in the United States on April 19, 2026 by klayton

  • Wiring harness
Size: Fuel Pump Relay Kit
Heavy duty. Well made. Good price
Reviewed in the United States on April 2, 2026 by larry weaver

  • Fits good does its job
Size: Fuel Pump Relay Kit
Good heavy made kit works well
Reviewed in the United States on October 3, 2025 by mike n.

  • Works great
Size: Fuel Pump Relay Kit
Worked flawlessly for what i needed
Reviewed in the United States on September 3, 2025 by Kayla and Danny Holtermann

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