Unusual customized Conn Bass Trombone. The designer of this instrument was a post doctorate engineering trombonist. It has Thayer and Conn dependent valves are that in the non-line configuration to optimize tone production when using the valves. A copper wire bead on the bell rim enhances the power capabilities of the bell. The slide has an additional brace that allows for a less tension in the slide hand. The instrument comes with two different lead pipes. Included is a Neotech trombone grip that distributes the weight preventing hand cramps. The slide is excellent and the horn is very free blowing in the low register.  Some of the tubing near the Thayer valve is not lacquered brass.
Tuning is done by two slides, the main tuning slide and the slide with the Conn valve on it. This slide intonates both the F and D valves together. The designer of the horn engineered it that way. I never had to change anything but the main tuning slide because of this design. If you want, you could use the other connecter that's adjustable to move the F/D tuning slide. I have never found a need to adjust as I had spot on intonation with the current configuration of the F and D tuning slide. It's designed so that both sides of the horn are in tune with each other and moving the main tuning slide moves the pitch of both the same. There is also an extra tuning slide should you want to remove the Conn valve and have a single valve bass trombone. Also included are two extra tubes that can be used with the extra tuning slide which will bring the F attachment notes down an octave in the single valve configuration.

On Feb-14-17 at 09:01:50 PST, seller added the following information:

Unusual customized Conn Bass Trombone. The designer of this instrument was a post doctorate engineering trombonist. It has Thayer and Conn dependent valves are that in the non-line configuration to optimize tone production when using the valves. A copper wire bead on the bell rim enhances the power capabilities of the bell. The slide has an additional brace that allows for a less tension in the slide hand. The instrument comes with four different lead pipes. Included is a Neotech trombone grip that distributes the weight preventing hand cramps. The slide is excellent and the horn is very free blowing in the low register.  Some of the tubing near the Thayer valve is not lacquered brass. The case is the original Conn bass trombone case that has had the mouthpiece compartment removed to accommodate the extra tubing.

Tuning is done by two slides, the main tuning slide and the slide with the Conn valve on it. This slide intonates both the F and D valves together. The designer of the horn engineered it that way. I never had to change anything but the main tuning slide because of this design. If you want, you could use the other connecter that's adjustable to move the F/D tuning slide. I have never found a need to adjust as I had spot on intonation with the current configuration of the F and D tuning slide. It's designed so that both sides of the horn are in tune with each other and moving the main tuning slide moves the pitch of both the same. There is also an extra tuning slide should you want to remove the Conn valve and have a single valve bass trombone. Also included are two extra tubes that can be used with the extra tuning slide which will bring the F attachment notes down an octave in the single valve configuration.

On Feb-14-17 at 09:04:01 PST, seller added the following information:

The case is the original Conn case with the mouthpiece compartment removed to accommodate the extra tubing. The bell is 9 1/2 inches in diameter and it actually has four different lead pipes.