Monoblock ball valves:

Monoblock ball valves are devices that comprise of three different flanged (in the most expensive models) or screwed-in (in the cheaper models) parts.

Monoblock ball valves can be made of different materials, depending on their usage. Stainless steel, carbon steel, F51, Hastelloy, Monel 400, bronze and bronzal are used for high pressure valves, while brass is used for low pressure valves.