--- product_id: 47024300 title: "50003R Automotive Set 5-Pin 30/40A 12V SPDT with Interlocking Relay Socket and Wiring Harness-5 Pack, 2 Years Warranty" brand: "nilight" price: "$31.63" currency: USD in_stock: true reviews_count: 13 category: "Nilight" url: https://www.desertcart.us/products/47024300-50003r-automotive-set-5-pin-30-40a-12v-spdt-interlocking store_origin: US region: United States of America --- # 40A max switching current Universal fit, easy install 2-year warranty protection 50003R Automotive Set 5-Pin 30/40A 12V SPDT with Interlocking Relay Socket and Wiring Harness-5 Pack, 2 Years Warranty **Brand:** nilight **Price:** $31.63 **Availability:** ✅ In Stock ## Summary > ⚡ Upgrade your ride’s electrical game with Nilight’s powerhouse relay set! ## Quick Answers - **What is this?** 50003R Automotive Set 5-Pin 30/40A 12V SPDT with Interlocking Relay Socket and Wiring Harness-5 Pack, 2 Years Warranty by nilight - **How much does it cost?** $31.63 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/47024300-50003r-automotive-set-5-pin-30-40a-12v-spdt-interlocking) ## Best For - nilight enthusiasts ## Why This Product - Trusted nilight brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Built to Endure:** Operates flawlessly from -40°C to 125°C with shock & vibration resistance - • **All-in-One 5-Pack:** Complete relay and socket sets for multiple upgrades or replacements with peace of mind - • **Powerhouse Switching:** Handles up to 40A at 14V DC for robust automotive control - • **Plug & Play Precision:** Unique male-female slot design ensures seamless, clean connections every time - • **Color-Coded Convenience:** Wiring harness with distinct colors simplifies installation and troubleshooting ## Overview The Nilight 50003R is a premium 5-pin SPDT automotive relay set designed for 12V systems, delivering a high switching capacity of 40A (normally open) and 30A (normally closed). Featuring a durable male-female interlocking socket design and color-coded wiring harness, it ensures easy, clean installation and universal compatibility. Built to withstand extreme temperatures and vibrations, this 5-pack includes a 2-year warranty, making it the reliable choice for upgrading or replacing automotive relays in lighting, starters, and more. ## Description Nilight 12V 5-Pin Relay with 5-Pin Harness Socket (30A NC/40A NO) A relay is an electrically operated switch which use a smaller current to control a larger current. Functions as automatic adjustment, safety protection and conversion circuit. Specification Contact Capacity Normal Switching Capacity (Resistance load) NO (Normal Open) 40A 14VDC NC (Normal Closed) 30A 14VDC Max. Switching Current 40A Max. Switching Voltage 30VDC Max. Switching Power 560W Performance Parameter Contact Material: Silver Alloy Contact Resistance: 50mΩ Max. Operate Time (at nominal volt.): 10 msec. Max. Release Time (at nominal volt.): 5 msec. Max. Insulation Resistance: 100MΩ Min. (DC500V) Initial Dielectric Strength: - Between open contacts: AC500V, 50/60 Hz 1Min. - Between coil and contact: AC500V, 50/60 Hz 1Min. Vibration Resistance: - Functional: 10 ~ 55Hz at double amplitude of 1. 5 mm - Destructive: 10 ~ 55Hz at double amplitude of 1. 5 mm Shock Resistance: - Functional: 20G Min. - Destructive: 100G Min. Endurance (operations) Mechanical (at 7, 200 ops. /h): 10, 000, 000 Electrical (at 600 ops. /h): 100, 000 Ambient Temperature: -40 degree Celsius ~ +125 Degree Celsius (no condensation) Application Pre-wired relay with harness socket, compatible with almost all kinds of automotive devices that use a 12V DC power source. Widely used for car lights, fog lamps, headlights, seat warming, windshield wiper, starter, fans, speakers, traction control systems, etc. Review: relays that actually work out of the box - Used these for some LED light work on my truck and every single one worked perfectly with no surprises. The wiring diagram printed right on the relay is super helpful when you're doing your own install and don't want to keep looking stuff up. Having the harness included means no splicing which saves a ton of time and makes the whole thing look cleaner. Really solid kit especially for a 5 pack at this price. Review: Fantastic - They work just fine, good pigtail, have screw-point, all as described and expected. ## Features - High switching capability: Normally open 40A/14V DC and normally close 30A/14V DC. Suitable for Nilight LED light bar wiring harness kit - Premium quality: Durable relay and harness socket with 5 wires; Made by high-grade materials to ensure superior quality and long lifespan - Male-female slot design: Unique male-female slot design, easy to connect the relay with harness socket, clean and neat after installation - Easy wiring: The relay sockets come with different colors for loads/accessories, simple and convenient wiring - Package include: 5 x relay and 5 x relay socket with wires.Fit type: Universal fit ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B0748F1JK4 | | Best Sellers Rank | #3,726 in Automotive ( See Top 100 in Automotive ) #2 in Automotive Replacement Starter Relays | | Brand | Nilight | | Brand Name | Nilight | | Coil Resistance | 50 Milliohms | | Coil Voltage | 12 Volts | | Connector Type | Plug-In | | Contact Current Rating | 40 Amps | | Contact Material | Silver Copper | | Contact Type | Spdt | | Current Rating | 40 Amps | | Customer Reviews | 4.6 out of 5 stars 3,403 Reviews | | Global Trade Identification Number | 00600537013346 | | Included Components | 5PCS Relay Harness Set | | Item Type Name | Nilight Automotive Relay Harness Set 5-Pin 30/40A 12V SPDT with Interlocking Relay Socket and Wiring Harness - 5 Pack，2 Years Warranty | | Item Weight | 8 ounces | | Manufacturer | Nilight | | Maximum Switching Current | 40 Amps | | Maximum Switching Voltage | 30 Volts (DC) | | Minimum Switching Voltage | 30 Volts (DC) | | Model | 50003R | | Mounting Type | Surface Mount | | Operation Mode | Automatic | | Part Number | NI-RE05 | | Specification Met | UL | | UPC | 600537013346 | | Unit Count | 5.0 Count | | Upper Temperature Rating | 125 Degrees Celsius | | Warranty Description | 2 Years Warranty | | Wattage | 560 watts | ## Product Details - **Connector Type:** Plug-In - **Contact Material:** Silver Copper - **Contact Type:** Spdt - **Current Rating:** 40 Amps - **Mounting Type:** Surface Mount ## Images ![50003R Automotive Set 5-Pin 30/40A 12V SPDT with Interlocking Relay Socket and Wiring Harness-5 Pack, 2 Years Warranty - Image 1](https://m.media-amazon.com/images/I/61QfU5CpR+L.jpg) ![50003R Automotive Set 5-Pin 30/40A 12V SPDT with Interlocking Relay Socket and Wiring Harness-5 Pack, 2 Years Warranty - Image 2](https://m.media-amazon.com/images/I/61h-eSTxDYL.jpg) ![50003R Automotive Set 5-Pin 30/40A 12V SPDT with Interlocking Relay Socket and Wiring Harness-5 Pack, 2 Years Warranty - Image 3](https://m.media-amazon.com/images/I/51Zyl0TZLLL.jpg) ![50003R Automotive Set 5-Pin 30/40A 12V SPDT with Interlocking Relay Socket and Wiring Harness-5 Pack, 2 Years Warranty - Image 4](https://m.media-amazon.com/images/I/614N9SFLlrL.jpg) ![50003R Automotive Set 5-Pin 30/40A 12V SPDT with Interlocking Relay Socket and Wiring Harness-5 Pack, 2 Years Warranty - Image 5](https://m.media-amazon.com/images/I/61SWi7NCSyL.jpg) ## Available Options This product comes in different **Color** options. ## Questions & Answers **Q: How long will this last with constant on and off pulses** A: Mechanical (at 7,200 ops./h): 10,000,000 Electrical (at 600 ops./h): 100,000 **Q: Is it possible to remove the metal mounting bracket so it can be used in a relay box?** A: The mounting tab can easily be removed however I don’t know if they would fit in a relay box **Q: I am looking for turn signal relay to correct hyper-flash with led bulbs on 2012 Honda Fit, with out having to put resistor at each location ???** A: Go to a truck stop and get an electronic flasher,it doesn't care how many lights you have in the system or how few. **Q: I want to use this to power my cooling fan when the ignition key is turned. If I wire off the battery will it work?** A: As long as 1. You wire the common (terminal 30) to your fan+, and 2. You wire NO (terminal 87) to VBat (through a fuse), You should be fine. That is pretty much how my car has these relays wired from the factory for the radiator fans. I assume you will connect terminal 85 to VBat through a fuse, and your ignition-control wire is a ground-interrupt connected to terminal 86 (otherwise, if your ignition-on wire is +12V/hot, you will want to connect it through a fuse to terminal 85, and simply ground terminal 86). I seem to recall these solenoid coils pull about 130mA at 12V when I tested them. ## Customer Reviews ### ⭐⭐⭐⭐⭐ relays that actually work out of the box *by M***C on April 5, 2026* Used these for some LED light work on my truck and every single one worked perfectly with no surprises. The wiring diagram printed right on the relay is super helpful when you're doing your own install and don't want to keep looking stuff up. Having the harness included means no splicing which saves a ton of time and makes the whole thing look cleaner. Really solid kit especially for a 5 pack at this price. ### ⭐⭐⭐⭐⭐ Fantastic *by S***Z on March 5, 2026* They work just fine, good pigtail, have screw-point, all as described and expected. ### ⭐⭐⭐⭐⭐ Awesome Product. *by K***. on March 24, 2026* Almost never give 5 Stars, but this one is well worth it. Awesome product. ## Frequently Bought Together - Nilight 50003R Automotive Set 5-Pin 30/40A 12V SPDT with Interlocking Relay Socket and Wiring Harness-5 Pack, 2 Years Warranty - 10 Pack Inline Fuse Holder 12V, Professional 12 AWG Waterproof Fuse Holder with 35 Pcs (5A/7.5A/10A/15A/20A/30A/40A) Standard Car Fuses, Giwiemi in Line Fuses Holders 12v for Marine Auto and Circuits - 12 AWG Inline Fuse Holder - 12 Gauge Fuse Holder for 30A Blade Fuse (6 Pack) --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.us/products/47024300-50003r-automotive-set-5-pin-30-40a-12v-spdt-interlocking](https://www.desertcart.us/products/47024300-50003r-automotive-set-5-pin-30-40a-12v-spdt-interlocking) --- *Product available on Desertcart United States of America* *Store origin: US* *Last updated: 2026-05-16*