Bearing stone for ropes. Pyramid shape with grooves up the sides and over the top in both directions. A label found wwith this object calls it a bearing stone and says "Giza, Mycerinus Pyramid Temple"; no number.
From Giza, G 4220 A. 1914: excavated by the Harvard University–Boston Museum of Fine Arts Expedition; assigned to the MFA in the division of finds by the government of Egypt.
Harvard University—Boston Museum of Fine Arts Expedition