This is an early model of a one-wavelength Eliza. You can see that it refuses to lose its inner bucketness.
The elastic strap helps hold the Eliza on the head, with the back tilted back onto the base of the skull and the front just above eyebrow levels. It doesn't matter if the red light gets into the eyes. I find it more comfortable to be able read or watch television while wearing an Eliza.
Despite its less than-magnificent-appearance, it gives a good spread of light around the head, and the foil insert reflects the lights a little. It all helps.
The instructions for making one of these are being completed. There is a list of what you will need already posted.