I have been using the Rubylith® RM3 is a high-tack ruby film coated onto 300-gauge polyester.
For some time now and I can not recommend it.
This type Rubylith does not hold up very well...
Very easy to scratch and tear, mine last less then a year!
I would go to Sloan's Woodshop
And get a couple of the Acrylic Sheets of the Transparent Colors #911 or the #997
These are what I have been using on my Laptops and they are GREAT!
If you are still looking forRubylith
scopestuff.com carries it!
Rubylith can be used to cover anything that emits light.
Its sturdy enough to be reused and flexible enough to cover flashlights, led lights, etc
and of course it's ideal for computer monitors.
It actually increases contrast on monitors for better seeing in the dark.
You won't believe how good this stuff works!
.
Rubylith® RM3 is a high-tack ruby film coated onto 300-gauge polyester.
Rubylith is normally used in graphic arts and screen-printing industries, however, it is an excellent product for amateur astronomers as well. Rubylith will produce very consistent results when used to create a night-safe red light out of normal white lights, unlike most quick-fix materials we've tried, such as red tape, paint, and thin cellophane.
Since it is bound to 300 gauge polyester, it holds it's shape well when cut and is easy to work with.