An ASTM A351 CF3 plug valve is a quarter-turn manual valve made from austenitic stainless steel with low carbon content. The material composition includes 18-21% chromium, 9-13% nickel, a maximum of 0.08% carbon, and balanced iron, along with small amounts of manganese, silicon, and molybdenum. These valves are designed for stopping or starting the flow of fluid, offering reliable on-off and diverting capabilities, and providing moderate throttling services.