Date: 1961. Owner unknown
The 20J has three valves. Notice in the text below that it doesn't say "Lustre-Conn finish". In spite of that, the finish on this instrument looks pretty good. The 20J was made between at least 1934 and 1980.
What Conn said in 1934:
The newest of Conn basses cuts the stroke nearly 33 per cent and gives the bass player an action just a trifle longer than that of a cornet! [...] Furthermore, the finger tips have been arched to fit the natural position of the fingers and have been moved 5/32 of an inch closer together. This gives the shortest, fastest, easiest-working valve action built into a bass and is a boon to all players. Equipped with celebrated Clickless Crysteel Pumps. Built with detachable, adjustable 24-inch bell tilted slightly upward, mouthpipe swung away from the bell stem, equipped with curved, swivel bit-all of which features give comfort in playing and clear view of the director. The intonation is the finest ever built into a bass. Immediately bought by such men as Chas. Barber, Waring's Pennsylvanians; Chas. Ford, Jan Garber; and Stanley Soboski, phenomenal bass, Fox theatre, Detroit. Large bore, BBb, 3 valves.
What Conn said in 1959:
Famous large bore bass, the standard of the world. Hydraulic expansion on every taper to protect the inside bore. Valves are 1/3 shorter than other basses. Valve stems are off-set to fit the fingers. Adjustable 24" bell interchangeable with straight bell. Mouthpiece, music lyre and adjustable tuning bit included. Fast, short action valves, clickless Crysteel pin guide valve pistons, extra mouthpiece bit for personal comfort. Highly polished brass clear lacquer finish.
Also Available: Satin silver plated with gold bell. Upright bell, highly polished brass lacquer finish. Upright bell, satin silver plated with gold inside flare.