Sometimes there are instruments in the ensemble other than those shown above.
This woodwind quartet is for 1 Flute, no Oboe, 1 Clarinet, 1 Bassoon, 1 Horn and Piano. Any additional instruments (Piano in this example) are indicated by 'w/' (meaning 'with') or by using a plus sign. The first number stands for Flute, the second for Oboe, the third for Clarinet, the fourth for Bassoon, and the fifth (separated from the woodwinds by a dash) is for Horn.
The bracketed numbers tell you the precise instrumentation of the ensemble. Rimsky-Korsakov Quintet in Bb Item: 26746 Following many of the titles in our Wind Ensemble catalog, you will see a set of numbers enclosed in square brackets, as in this example: