Abstract: A folding brush comprises a case having parallel first and second walls respectively having first and second interior faces spaced from each other to form a cavity. The first wall includes a matrix of cylindrical like slots extending between the first face and a third face on the exterior of the first wall. A frame slides along a longitudinal axis in the cavity between a first retracted, locked position and a second fully extended, locked position. Multiple of tapered, unifilar, generally straight bristle tufts have bases mounted in the frame so longitudinal axes of the tufts rotate together from a first retracted angle displaced slightly from the frame longitudinal axis to a second fully extended angle approximately at right angles to the frame longitudinal axis in response to the frame sliding between the first and second longitudinal positions.