Real Techniques Color Correcting Set: “EVENLY APPLY + BLEND COLOR CORRECTING CONCEALERS. Make color correcting easier with the color correcting set. Apply, buff, and blend color correcting concealers for an even tone complexion before makeup application. Each brush corresponds to a key correcting concealer color to avoid color mixing.”
A brilliant idea for keeping colour correcting cosmetics separate and clean by allocating one brush for each correction colour. Some faces need correcting in several different colours and I gave seen makeup artists use the same brush for different colours, needlessly diluting them and making extra work for themselves.