As stated a the museum’s information card: “Stone engraved with standard measurements, giving metrical units in half an orgyia (“span”), which is the span of the open arms, the pechys (“cubit”) (0,487m), the spithame (open palm) (0,242m), and two standards of the foot (0.0302m and 0.322m). The second of these, in form of a rule, was used as a basis for the calculation of the cubit, the palm and the span. There is another relief with standard measurements in the Ashmolean Museum, Oxford, though this was probably a dedication. Found built into a chapel on Salamis (4th c. BCE)”
Information card, exhibited at the Archaeological Museum of Piraeus, Greece.