One more "antique" virtual reality helmet, now it's Liquid Image MRG2.2 from 1993. It's monoscopic, but have very big field of view: about 100 degrees horisontal and 60 vertical.
When used with proper content, this helmet provide very immersive visuals (but low resolution), and high quality sound.
Field of view is so big, that it partially cover peripheral vision, and this tricks vestibular system of the user.
This HMD have almost unbreakable carbon-like shell, which together with optics and internals weight's about 3 kilograms!