Generally they are used in a modulated way, that means, where the glass-metal soldering cannot be carried out directly.
To fix them we use tin or tin/gold soldering and it is used for passing energy through a metallic wall or electric signs, for a tension up to 25 ampères.
There are standard models or we can make them in accordance with customer´s drawing and requirements. Its applications are mainly for Electronic, Microelectronic, Hyperfrequency, etc.