NEF30 type control buttons with metal bodies are designed to be built into standardized holes Ř30, 5 mm made in consoles, control and signaling boards or directly in the bodies of machines and devices. NEF30 type buttons have a modular structure. Each push-button consists of: a driving element called the push button a switching element consisting of one, two or three connectors attached to the drive. The NEF30 pushbuttons are mounted using fastening nuts, without the need to separate the drive and connectors.