He saw the Prophet (ﷺ) raise his hands when he bowed, and when he raised his head from bowing, until they were in level with the highest part of his ears.
Sunan an-Nasa'i Book 12, Hadith 28
← Previous Hadith "My father told me: 'I prayed behind the Messenger of Allah (ﷺ) and I saw him raise his hands when he started to pray, and when he bowed, and when he said: Sami' Allahu liman hamidah (Allah hears the one who praises Him)" like this.'" And (one of the narrators) Qais pointed towards his ears.

Sunan an-Nasa'i Book 12, Hadith 27 Next Hadith → The Messenger of Allah (ﷺ) used to raise his hands until they were in level with his shoulders when he started to pray, and when he raised his head from bowing he did likewise, and when he said: Sami' Allahu liman hamidah (Allah hears the one who praises Him)" he said: "Rabbana wa lakal-hamd (Our Lord, to You be praise)" and he did not raise his hands between the two prostrations.

Sunan an-Nasa'i Book 12, Hadith 29