AVR ISP Shield Arduino Atmega328p Bootloader WriterModule features:
1- Plug this expansion board on the arduino UNO motherboard
2- You can program the bootloader for the Atmega328p in-line chip.
3- You can also use the cable to program the bootloader to other Arduino or AVR chips with ISP interface.
4- No longer need professional programmer, or other programming tools
5- It is not necessary to connect the wrong wire on a single chip
6- Don't worry about locking the chip with mismatched fuses.
For details, please refer to the official arduino information: https://arduino.cc/en/Tutorial/ArduinoISP