Four mirrors plus a central axis view give a complete view of the interior of the eye. Unique "depth dots" mark each mirror at the base for easy orientation. One dot, 62° (anterior chamber angle); two dots, 67° (ora serrata); three dots, 76° (mid-equator); four dots, 80° (mid-peripheral area). The mirrors provide fields of view that overlap completely. Gonio mag .80x. Gonio laser spot mag 1.25x.