Which tubes in Zone VI coldlights?

[Claude Sapp]

Just wondering, does anyone know which tubes, or how to tell which tubes, are in Zone VI coldlights? My Beseler 8x10 is clearly stamped W45 right on the tube, but my 4x5 and 2x3 Zone VI coldlight tubes are not identified in any way that I can see.

[Ken Lee]

These guys (http://www.aristogrid.com/prod02C.htm) may know:

Aristo Grid Lamp Products
400 Captain Neville Drive
Waterbury, CT 06705
Tel: 203-575-3425 Fax: 203-575-3456

[RichardRitter]

Zone VI used the blue graded paper tubes.