Rare Black All Over Birkis Birkenstock Pebbled Leather Adjust Strap Buckle 40 S

Look New (soles & everything makes me think that these are new) Pictures actual Sandals Black All OVER Embosed print like pebbles With 3 Adjust Adjustable Straps Buckles for size On the soles size says 40 S ( not sure if women or men) Measurement from middle across soles about 11" From what I understand 40 ( womens 9 - 9.5 or mens 7 - 7.5 NOT SURE) What the S stands for They Are different the soles & embed your feet is rubber and leather upper Please ask any questions that I did not know to provide