Thermosetting plastics include phenol-formaldehyde resins known as bakelite. Phenol-formaldehyde polymers are rigid and heat stable up to 150 degrees Celsius, with low thermal conductivity and good electrical insulation. They are used in electrical components like plugs, sockets, and switches. Amino-formaldehyde resins include urea-formaldehyde and melamine-formaldehyde, which are also hard and rigid with electrical insulation properties. Urea-formaldehyde and melamine-formaldehyde resins find applications in electrical devices and circuit breakers. Other thermosetting plastics such as polyesters, vinylesters, epoxies, and polyurethanes are used in applications like safety helmets