This document appears to be a catalog for Harmony brand electrical control components made by CÔNG TY CỔ PHẦN THIẾT BỊ ĐIỆN HOÀNG PHƯƠNG. It includes 22mm pushbuttons, selector switches, pilot lights, and other control devices. The catalog provides product specifications, installation instructions, and reference pages listing the company's complete range of XB4 metal and XB5 plastic pushbuttons, selector switches, pilot lights, and accessories.