'Anse Volante' is a technique, Giorgio Ferro used for A.VE.M. in the 50s and which has influenced the style of that time. Dino Martens developed this technique for Salviati in the 30s.
The still hot vase is pressed partially onto a metal plate to press the layer together at a certain place. At that, a hole is drilled in the glass wall and the vase is extended further with a machining tool and formed. This technique needs very much technical experience.