A fourth valve extends the range of this step-up model. The excellent intonation of the YBB-321 helps to foster a feel for correct pitch in beginning and intermediate players. Hand-lapping achieves the perfect balance between airtightness and smooth action. Hand-lapping is a time-consuming finishing process which results in superior valve fit for noiseless, responsive action and easy tone changes. The responsiveness of the YBB-321 assists beginning players in learning the phrasing of the tuba. Case included.