Origin, standards and world standard (ISO 1724)

What is a 7-pin plug?
The 7-pin plug for trailers, officially defined in the ISO 1724 standard, has been the standard for basic lighting of trailers, boat trailers and industrial trailers for decades.

This connector was developed in the 1960s when Europe needed a single, uniform solution for vehicle and trailer lighting. Before that, each country used its own systems—leading to incompatibility, additional costs due to malfunctions, and safety risks.

The ISO standard provided for:
• International interchangeability
• Reliable electrical connection
• Easy installation
• Lower production costs

For international supply chains, standardization isn't a detail — it's risk management .

Why ISO 1724 is still relevant

Despite the rise of 13-pin systems, the 7-pin connector remains dominant worldwide in, among others:

• Construction logistics
• Agricultural applications
• Industrial transport trailers
• OEM production of trailers

For many applications, the 7-pin plug is technically more than sufficient — without unnecessary complexity.

ProShen® as a manufacturer and sourcing partner

ProShen® supplies high-quality 7-pin connectors according to the ISO 1724 specification :

• OEM quality
• Corrosion-resistant materials
• Possibility of custom branding
• Private label production
• International compliance

Our combination of European quality control and production expertise in Asia enables us to achieve economies of scale without compromising reliability.