Inv. Card supplies the reading made by Krasotkinа, Bilimovich under the supervision of I.I. Tolstoy, dated February 1948: "either 21 or beginning of some word." Indeed, the Ionic numeral system allows to read number 21 here. Could it refer to quantity, price or volume? Perhaps more likely - an abbreviation of personal name (probably the owner's). There are a few personal names starting with ΚΑ. Most likely, the text was written on the complete pot, but inscription on a sherd cannot be excluded - the text is centered on the fragment relative to the breaks. Johnston (1979, 159, type 11F) identifies trademark ΚΑ and ΚΑΙ. (i) ΚΑ alone on BF pots, including on 5th century pots.