dXdT Music Products is the sole producer and distributor of rotary woodwind fingering charts. These products replace difficult to use fingering charts provided in some music books for flute, clarinet, saxophone, and recorder. The rotary products are compact, made of durable plastic and they provide a large, intuitive, and unambiguous display. They include common alternate fingerings and the circle of fifths. They can even be used to easily transpose music. The products are ideal for teachers to use in the classroom and as a classroom resource. Each student of woodwinds should have one to keep with them.