Linered version of tape 425, available as die-cuts for window masks during paint stripping.
Window masks, die-cuts for tape 427, are exact size, allowing for the outer edge of the adhesive to come in contact with the metal frame.
The adhesive never should contact the highly sensitive and expensive Plexiglas window, because some adhesives could leave a residue or even craze the window surface.
Only the soft liner of the tape will come in direct contact with the window.