TromboneChat

I bought this inexpensive trombone yesterday and was told it was a Bach trombone, the bell says Olds Ambassador, Fullerton, CA. What I need help with is identifying the tuning slide. It is shaped like an Olds trombone but it does NOT have the "Olds" label on the weight.
Could this trombone be a knockoff?

Who knows what you got. It is certainly NOT a "Bach trombone."

I want to upload an image of my tuning slide but don't know how. Seems like I need the forum admin to approve it first. Who is the Admin I need to contact for this forum?

A-15 Ambassadors are actually pretty distinctive in appearance.

Some have an oblong counterweight mounted to the tuning slide brace, like this:
Others have a round counterweight attached to the tuning slide crook, like this:
The braces (with the exception of the handslide brace on all but the earliest examples) are not round, but have a flattened oval cross-section. The handslide brace (in all but the earliest examples, as noted above) is round and is one piece, with no provision for length adjustment.