Mil (or military) spec circular connectors are a type of electrical connector made to meet the toughest of requirements in harsh environments.

What are Mil-spec circular connectors used for?

Originally designed to meet military specifications, mil-spec circular connectors are used in rugged environments in automotive contexts, mobile equipment, and oil and gas applications. They are specially designed for durability and resistance to vibration, corrosion and so on depending on the application.

Types of Mil-spec circular connectors

Some of the most common specifications and standards include:

Series I and Series IV connectors have a fast disconnect system. They offer high resistance to vibration and are also ideal for environments that experience strong winds and high humidity.
Series II connectors have a low profile, so are used when weight or space is limited, or in low-vibration situations.
Series III connectors can be used in high-temperature situations where good resistance to vibration is also required, as well as in environments with high winds and humidity.