These horns were produced to celebrate Keilwerth's 75th anniversary in 2000. Allegedly, only 142 altos and 144 tenors were built. However, considering you see a #162 horn in the below list, I think the numbers are either a bit off or we're talking about #162 out of 286.
The bow, bell, and keywork of these horns are silver plated. The body is black nickel plate.
Some of these horns have really nice looking rosewood "pearls," as you can see at SimplySax and on Stephen Howard's website.
If you want to change how many album pictures per page, use CTRL+ and CTRL- (Command + and Command - if you have a Mac). 80% looks great on my 4K monitor.