Brass ball valves are durable, corrosion-resistant valves made from brass, typically used for regulating the flow of water, gas, or other fluids in low to medium pressure systems. They feature a spherical ball with a hole in the center that rotates to control fluid flow, offering reliable shutoff and smooth operation. Brass ball valves are commonly used in plumbing, heating systems, and irrigation applications due to their strength, affordability, and ease of use.