This beginner soldering kit contains a heart-shaped pcb and 12 red LEDs that flash in a random pattern The user can touch the board on the center of the heart to increase the flashing rate of the LEDs All component parts are included with the kit along with an assembly manual (manual is in English) A 9V battery is required (not included). As an alternative to battery power, you may use our 9V/400mA wall adapter (sold separately, part number 16DPMW270013).