Specifications

• Conductor: Stranded bare copper

• Insulation: PVC (Polyvinyl Chloride)

• Voltage Rating: Typically up to 60V

• Standard Temperature Range: -40 to 80 degrees, some variants up to 105 degrees

• Standards: Meets SAE J-1128, Ford M1L-56A and Chrysler MS-3450 specifications 

GPT wire (General Purpose Thermoplastic wire) is a widely used type of automotive primary wire designed for low-voltage electrical applications in vehicles such as cars, trucks, boats, motorcycles, and trailers. Here's a detailed breakdown of its characteristics and uses:

🔧 Construction

Insulated Wire Made in the USA

• Conductor: Stranded bare copper, which offers flexibility and good conductivity

• Insulation: PVC (Polyvinyl Chloride), providing resistance to abrasion, oils, chemicals, and acids

• Temperature Range: Typically from -40°C to +80°C (or -72°F to 153°F depending on the source)

• Voltage Rating: Up to 50–60 volts, suitable for low-voltage automotive circuits

• Maximum amps 18 gauge 7 amps

• Maximum amps 20 gauge 5 amps

• Maximum amps 22 gauge 3 amps

  Amps=Watts/Volts

  Since most automotive systems run on 12 volts, here are a few examples:

  • Standard halogen headlight (55 watts):
    5512≈4.6 amps1255​≈4.6 amps

  • LED light (20 watts):
    2012≈1.7 amps1220​≈1.7 amps

  • Brake light bulb (21 watts):
    2112≈1.75 amps1221​≈1.75 amps

🚗Applications

• General circuit wiring in vehicles

• Trailer repair

• Add lights to your motor home

• Low voltage lighting around the house

• Motorcycle lights

• Motorcycle repair

• Boat lights

• Automotive lighting

• Doorbell wire

• Trailer wiring

• Interior lighting

• Car audio installations

• Heavy duty wire for your home, motorcycle, RV and lighting

• Custom wire assemblies for automotive projects

✅ Advantages

• Flexible and easy to route through tight spaces

• Resistant to common automotive fluids

• Cost-effective compared to cross-linked polyethylene (XLPE) insulated wire

• Can be customized with stripes or printed jacketing for identification