40-650 are connectors (also known as 40-650 coaxial connectors) used for joining shielded coaxial cables for medium-power RF applications. They have an operating range of DC to 250 MHz, voltage rating of 500V, and a current rating of 3 amps. They feature male and female connectors, with the male being slightly larger than the female. The exterior of the connector is colored red and white, and the interior contact is silver-plated. 40-650 connectors are commonly used in various low-frequency applications, such as radar, machinery diagnostics, two-way radio systems, security systems, and data transmission.