Hi Group, I have a Nelson-Wiggen Style 4X.  It has a total of
28 xylophone bars.  The xylophone scale is

                      E F F#
G G# A A# B C C# D D# E F F#
G G# A A# B C C# D D# E F F# G

The manufacturer appears to be the Kohler-Liebich Co., Chicago.

Jack M. Conway