Our instrumentation abbreviation format is as follows: 111.11+TPRH
1st digit = trumpet | 2nd digit = horn | 3rd digit = trombone
4th digit = euphonium/baritone (trombone) | 5th digit = tuba/bass trombone
T = Timpani | P = Percussion | O = Piano | R = Organ | H = Handbells
Thus, the code 211.01 indicates music for a brass quintet consisting of two trumpets, one horn, one trombone and one tuba. Additionally, the code 211.01+TP indicates music for brass quintet, plus Timpani and Percussion.