What Conn says:

Here is a rare instrument: the 35B Victor D trumpet. Produced between 1961 and 1969 on special order only. It has a #½ bore, which is 0.425″ and bottom spring valves. Interestingly, like the 25B Victor C trumpet Conn chose to base the design of this instrument on the 1955-1957 Victor and not the Connstellation. Perhaps this is telling. Afterall, this is a professional-only instrument, amateurs and high school bands usually don’t require a D trumpet, making the choice of design noteworthy. Please see Comparative quality of Conn instruments, part 2 for a longer discussion of this. Also notice that this instrument doesn’t have any nickel trim, and the 2nd slide is at a right angle to the valve casing in stead of being angled towards the player as is usually the case for instruments in the 1950’s and 1960’s. It also seems to me that when one were to compare the 25B Victor C trumpet, this 35 Victor D trumpet and the 2A Victor (!) Eb cornet, you would see the same design in all of these instruments.  Small dent on the bell, I’m hoping to have it repaired before it’s sold.  Comes with the original case and a original constellation 9B-N mouthpiece in  a combination of gold, silver plate.