A microscope head with two eyepiece lenses, one for each eye.  Generally this term is used in describing a high power (compound) microscope.  With a low power microscope we say "stereo" head because, unlike the compound microscope, the stereo has a separate objective lens for each eyepeice lens, producing two independent paths o [..]

Two eyepieces, usually on a slide mechanism and can rotate 360°. The interpupillary distance is adjusted side-to-side, by sliding the eyepieces towards and away from each other.