The Messenger of Allah (ﷺ) said: I was commanded to prostrate myself on the seven (bones) and forbidden to fold back hair and clothing. (The seven bones are): forehead, nose, hands, knees and feet.
Sahih Muslim Book 4, Hadith 261
← Previous Hadith I have been commanded to prostrate myself on seven bones:" forehead," and then pointed with his hand towards his nose, hands, feet, and the extremities of the feet; and we were forbidden to fold back clothing and hair.

Sahih Muslim Book 4, Hadith 260 Next Hadith → "When a person prostates, he prostates on seven part of the body: His face, his hands, his knees and his feet."

Sahih Muslim Book 4, Hadith 262