Pre-loaded with the Arduino Optiboot (Uno 16MHz) Bootloader; ATMega328 8-Bit Processor in 28 pin DIP package; Operating voltage: 1.8v to 5v; RoHS compliant; The ATmega328 with Arduino Uno Optiboot Bootloader contains the bootloader used on the Arduino Uno, with small modifications.
This will re-flash the bootloader in selected chips. Only some Arduinos are supported to run the sketch. It has been tested on a Uno, Mega2560 and Leonardo. Supported target chips are: Atmega8 (1024 bytes) Atmega168 Optiboot (512 bytes) Atmega328 Optiboot (for Uno etc. at 16 MHz) (512 bytes) Atmega328 (8 MHz) for Lilypad etc. (2048 bytes)