Balloon whisk. Aline Ponce / Pixabay.com / 2016 / CC0 1.0
Balloon whisks (aka Piano Whisks) have many wires to form a balloon-shaped cage of tines.
The tines are further apart and thinner than for a sauce whisk.
They are good for whipping egg whites and anything light in which the emphasis is to introduce a great deal of air.
They were traditionally made of metal, but now they made be made of plastic, or of metal and have the tines coated with plastic to inhibit rust.
Plastic balloon whisk. © Denzil Green / 2005