Developed in cooperation with Mel Culbertson, this 6/4 tuba is based on the successful F-Tuba 45S-LP, but is more oriented towards the European taste with its 6 valve setup. It features a .748" Bore with a .787" 4th Valve Bore and .767" 5th and 6th Valve Bore in a 4 front action large piston and left hand 5th (long wholestep) and 6th (long halftone) rotary valve design. It also features a 2nd valve slide trigger for easy intonation adjustment.