I opened it up at home and saw the Shin-ei logo on the insides of the bottom plate:

It works, but the wah pot's a little scratchy. I was expecting it not to work at all.
Does anyone know what year these were made?
Some info:
http://www.effectsdatabase.com/model/kent/shinei/wah
http://www.effectsdatabase.com/model/sh ... panion/wt1
http://www.dirk-hendrik.com/shin-ei.html
More pictures (including a schematic):





I don't know how accurate the schematic is. It shows a 50K wah pot, but the pot in the pedal is 100k.