ZEff double trigger Performance bass trombone provides the classic dark, weighted sound that is the anchor to any low brass section. Professional features include a large 9.5” rose brass bell, which allows for a broad, colorful sound, more volume and more natural production of the lower partials. The zeff dual features a double rotor, independent valve system, which affords the player an extra set of slide positions to aid tuning and make natural slide changes. In the Blessing tradition, the zeff bass trombone provides a reliable and affordable option for student and mostly professional use that will encourage musical growth and development.