Breakout box

A breakout box serves as a troubleshooting tool to determine the wiring of an electrical connector interface on a networking device or computer.

Typically, a breakout box is inserted between two electrical devices to determine which signal or power interconnects are active.

Breakout boxes are specific examples of a more general category of network testing equipment called "status monitors".

They generally come with several kinds of connectors and are quick and easy to use for isolating problems with serial transmission connections in networking, telecommunications, and industrial settings.

[2]The term breakout box is derived from the mechanical enclosure in which a connector's aggregate connections are separated (i.e., broken out) into the individual signal or current-carrying wires or cables.

Tesuto Systems T1000-37 Breakout box of commonly used D-sub connectors. Breaks out each connector contact to easy to access test points.
T1000-37 Tesuto Breakout box employing commonly used 37 position D-sub connectors that break out to banana jack test points.
A four-port serial (RS-232) PCI Express ×1 expansion card with an octopus cable that breaks the card's DC-37 connector into four standard DE-9 connectors
Example of a pocket-sized RS-232 breakout box that features switches to reconfigure or patch any or all the active circuitry. This unit has one DB25 male and one DB25 female RS-232 connector