JD1912 Car Relay Harness 12V 40A 4 Pin SPST 12AWG Harness Sockets with Color-Labeled Wires for Automotive Truck Van Motorcycle Boat (Pack of 2)

Used this relay to wire up the air compressor for my air bag suspension on my pickup, and it worked flawlessly. The color-labeled wires made installation super straightforward, and the 12AWG wiring feels solid and well-made. Handles the load without any issues, and it gave me peace of mind knowing the compressor is properly wired and protected. Great value for the quality—definitely recommend it for any automotive accessory setup.

I recently acquired the Gebildet JD1912 Car Relay Harness 12V 40A 4 Pin SPST Harness Sockets with Color-labeled Wires for Automotive Truck, and I must say, it has exceeded my expectations. This well-crafted harness has truly impressed me with its quality construction and user-friendly features, particularly the color-coded wires that greatly simplify the installation process.I utilized the Gebildet JD1912 Car Relay Harness to integrate a new light bar onto my truck, and the results were outstanding. The 40-amp relay provided ample power for my light bar's requirements, ensuring optimal performance. Furthermore, the wires included in the harness are adequately thick to handle the electrical current without risking overheating or any compromise in functionality. The combination of durability and reliable performance instilled a sense of confidence in the harness's ability to handle the demands of my lighting setup.A notable advantage of the Gebildet JD1912 Car Relay Harness is its versatility. This harness is accompanied by a selection of connectors, allowing for a wide range of applications. I was able to seamlessly connect my light bar to various components in my truck, including the battery, fuse box, and switch, thanks to the inclusion of these well-designed connectors. This adaptability adds immense value to the harness, making it a practical and versatile solution for automotive enthusiasts seeking reliable electrical connections.Overall, the Gebildet JD1912 Car Relay Harness stands as a remarkable product. Its superior construction and thoughtful design ensure a seamless installation process, even for individuals with limited technical expertise. The convenience of color-coded wires greatly simplifies the setup, reducing the likelihood of errors or confusion during installation. The reliability of the harness, combined with its compatibility with a variety of applications, demonstrates its worth as a top-quality product in the market.While the Gebildet JD1912 Car Relay Harness boasts several strengths, it is important to consider some potential drawbacks. One aspect to keep in mind is the relatively higher price point compared to some alternative brands. However, this price difference can be justified by the harness's superior quality and reliable performance. Additionally, it may be slightly less readily available than more widely recognized brands, although it is certainly worth the effort to seek out this exceptional product.Taking into account the advantages and potential limitations, it is evident that the Gebildet JD1912 Car Relay Harness is a commendable choice. Its durable construction, user-friendly features, and adaptability make it a standout product in the realm of car relay harnesses. I wholeheartedly recommend this harness to anyone in search of a reliable and convenient solution for their automotive electrical needs.

I used these for the circuitry on 1970's Jeep Wagoneer rear power window and they worked flawlessly. I would EASILY buy these again. The recepticles are well made and include small metal mounting tabs which I did not use. The relays work. The wiring is true to the stated gauge sizing. I paid about $8 for the pair of these in April 2025. At $4 each, these are a good value assuming they last. These will be getting near daily use so I will report back, especially if these prove to be unreliable.

Two for the price of one is always a great deal! The price is very good for this power relay switch. The device is properly sealed in a case to make it waterproof. It comes with a connector that likewise seals well when plugged in to the relay.This is rated perfectly to carry the current and power needs for all of my motorcycle accessories. I wanted to isolate all of my add-ons so that when the bike sits dormant the drain on the battery is greatly reduced. My circuit includes this relay between my accessory terminal to a power distribution block with fuses. When the motorcycle is turned on the relay engages sending power to the distribution block. The block has six accessories wired with individual fuses on each circuit. When the relay engages power is available to the block and sent to each of the six accessories.By isolating the power to the accessories with the relay they cannot draw even a trickle current from the battery when the motorcycle is powered off.The relay has a diagram on the top of the case to show the circuit but these are stamped into the case and very difficult to read. More importantly, the relay does NOT come with any directions whatever! There are four leads/wires coming from the included plug which are color coded. I was able to determine by testing with a meter which lead was Common, Positive, Line and Load. The plug terminals are uniquely oriented so that it is not possible to insert the relay incorrectly which I deeply appreciated.You need to have a thorough understanding of circuitry to properly install and use this. Two wires power the relay itself, the other two break/complete your desired circuit power. Make sure your power demand is aligned with the ratings of this relay. It is robust and spec'd for most common power needs for outdoor vehicle accessories.NOTE: The photo shows three items, the relay and plug which are included, and the power distribution block with IS NOT included. I just showed to illustrate my setup.Prior to installing this relay and distribution block I had 7 or 8 different wires and terminals connected to the positive/negative terminals on the battery. What a rats nest! This new circuit setup reduces the wires directly connected to the battery, provides circuit protection and clean wire routing. In operation the relay works flawlessly. Aside from the lack of instructions I feel this is a great value as the product works well, comes with the necessary plug and you get TWO of each.

They properly, good quality wiring, mounting was simple, the only downside was the plug in connector has no locking clip, a zip tie fixed it.

The relay is somewhat bulky, but it's a perfect option for an underhood environment or perhaps even a marine environment. I'm using it in the engine compartment of my car. I'm happy with it. Works as expected.

Works great. Used to wire automotive accessories. Good quality.

Works as expected. However these things are unnecessarily large in dimensions. If you are working in a tight space like on a motorcycle these are really too big.