Bergstrip (Male and Female Connector)
This 2.54MM pitch 40 Pin Male and female Header Strip Breakable is useful for custom PCBs or general custom headers. They are Stackable – End to End and Side to side. Can be manually broken for length needed. It has a current rating of 1 Amp.
This pin header is an ideal connector for the PCB board and integrated circuit used widely in the computer and breadboard. Male to Female, Male to Male and Female to Female jumpers are used for connections with development boards so as to provide temporary connections. Bergstrips are generally soldered to PCB, development boards and LCD displays so as to connect Jumper wires.

The above image shows male and female burg stick connector
Berg Strip is a commonly found connector in all kind of circuit boards. It is also called as Berg Stick because of its stick like structure. Berg Strip is designed by the Berg Electronics Corporation at Missouri.
The Berg Strip is very light and compact and it can be easily assembled to a circuit board. One of the main features of the Berg Strip is that, unlike other connector a designer can modify the connector module as per his imagination. The Burg Strip can be easily cut off into pieces having required pin numbers, and then the pieces can be arranged in a single row or in a row and column manner. This freedom makes the Berg Strip all-time favorite of the circuit designers.
Types of Berg
Male berg

This 40 Pin Male Break Away Header has the industry standard spacing of 2.54mm and are designed for soldering directly into printed circuit boards (PCB). They are supplied Best for extension of pins of Microcontorllers and ICs
Female Berg

This is 40 pins single row female berg strip/header. It can be cut into any desired sizes with the wire cutter. The pitch for this header is standard 2.0mm.
. They come with a predefined number of pins. The designer then cut off only the required number of pins and assembles to the circuit board. It can act as wire-to-board connector also; we can solder the wire to either of the connector pins and fix the other connector to the circuit board. When we solder wires to the pin of both the pair it can function as a wire-to-wire connector also. Normally they are used as board-to-board connectors with the male connector are soldered at the periphery of the circuit board and the female connector is assembled wherever another board is intending to be connected.

They are designed for high reliability and quick assembly. They are also very cheap connectors. The Berg strips are used to carry both power and data.
Berg strip found its application in almost all kind of circuit modules, like GSM module, GPS module, Xbee module, and LCD module and in all kind of circuit boards.
Sample specification:
Contact resistance ———————— 30 mille ohm
Current rating —————————— 1 A
Insulation resistance ——————— >1000 mega ohms
FEATURES:
- 1 Amp current rating
- Number of pins: 40
- Connector type: Pin Strips Male-Female Pair
- Insulator Material: Nylon
- Contact Material: Brass
- Square Posts.
- Stackable – End to End and Side to side.
- Can be manually broken for the length needed.
- Standoffs allow cleaning of solder contaminants.
APPLICATION:
- For connecting Male to Female , Male to Male and Female to Female jumpers.
- Bergstrips are generally soldered to PCB, development boards and LCD displays so as to connect Jumper wires.
Reference:
https://www.engineersgarage.com/tutorials/board-to-board-connector/
https://rarecomponents.com/store/1222
https://www.banggood.in/buy/male-female-berg-strips.html
https://learn.sparkfun.com/tutorials/connector-basics