D-sub MIL Spec connectors are a type of electrical connector that are commonly used in military, aerospace, and industrial applications. These connectors are designed for reliable connections, high levels of vibration, and extreme temperature and environmental operating conditions. D-sub MIL Spec connectors are constructed of highly durable metals, including stainless steel for contacts, and aluminum or steel for shells. These connectors are available in various contact arrangements and sizes, with the most common being 9-contact and 15-contact connectors. They also feature a threaded locking feature that ensures that a secure connection is maintained during vibration and environmental exposure.