Using a Flat Brush

A flat brush is, as the name would suggest, one where the bristles
are arranged so the brush is quite wide but not very thick.
The length of the bristles can vary, with some flat brushes having long
and some very short bristles. (The latter is also called a square brush.)
When buying a flat brush, look for one where the bristles have a spring to them,
or snap back when you bend them gently.

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