This set of Schneider 138mm diopters are great for achieving close/macro focus when using regular prime or zoom lenses.
Really gets you out of a pinch with using anamorphic lenses that traditionally have further close focus than spherical lenses.

These optics are compatible with most rail-mounted matte boxes, in particular the Arri “MB” series. We also stock a dioptre tray for use with Arri LMB matte boxes.