Conn 8G/9G Italian Model Valve Trombone
Date: 1900's-1920's (Drawing)
The 8G is the Low Pitch version of the instrument, the 9G is the High Pitch model.
What Conn said in 1924:
The Italian model pictured above was built especially for the many Italian soloists who have always played this yupe of instrument in the famous bands of Italy. Their preference for the elevated bell can be readily appreciated, as it throws the tone upwards and outwards even though the valve part be held in a slightly drooping position.