This document provides an overview of the typical components found in a gas insulated substation (GIS), including: enclosures made of aluminum alloy; conductors made of aluminum alloy; SF6 gas used for insulation and sealing; insulators that act as gas barriers; SF6 accessories like density sensors, valves, and pressure relief; circuit breakers; disconnectors; earthing switches; current and voltage transformers; and surge arresters. It also mentions gas insulated lines/bus and references further topics like GIS construction, maintenance, and its role in electric grid applications.