Rath R4 Custom Bb/F Tenor Trombone with Rotax Valve

The medium/large bore R3 trombone and the large bore R4 are available with an F valve section with the designation of R3F and R4F.

Michael Rath also offers the R4 and R4F models with "in slide" tuning,

Two valve choices are available, both Swiss designed: the René Hagmann valve or the Willson Rotax valve. The Hagmann is free flowing and well balanced between open and closed operation. The Rotax has a more traditional feel, offering a little more resistance, preferred by many players.

Because of the modular construction of Michael Rath custom trombones you can remove the valve section and replace it with a detachable gooseneck, available as an option, creating a straight tenor trombone. Similarly, if you already own a “straight” R3 or R4, you can purchase just the F valve section to fit your instrument.