What is a Talmudic cubit?
A Talmudic cubit is sometimes said to be 555 millimeters or 21.1 inches. It is hard to know how correct this is.
Ancient Israelites seemed to have two different standards for a cubit in the Bible. In Ezekiel, the cubit, it is suggested, is equal to five palms while elsewhere the cubit is six palms. A palm is equal to the width of four fingers.