You use them to pick the leaf up and to apply it to the object to be gilded, above all if the surface is uneven (inlays, moldings, friezes). They are available in various shapes and dimensions; they are always made of two types of animal hair:
Vaio hair comes from the tail of a particular type of squirrel, called Vaio; it is very soft, shiny and flexible.

Badger hair: this kind of brush (large and flat) is mostly used in the tapping technique, a very antique one mostly used by the cabinetmakers.

The tapping technique achieves a perfectly smooth surface without any brush mark, thanks to its forked hair structure like a swallow-tailed flag, which gives a very soft effect.