This is AC Inverter. Input 12VDC from car battery to output 220V AC 50Hz or 60Hz at Square wave signal.
The main part is IC CD4047 (or IC 4047 Series) and IC LM358 and Transistor 2SC1061 and 2N3055.
The transformer is 12V-012V Primary : 220V Secondary.
and current 3A up for power output than 100W