Sayyiduna Ibn Umar (may Allah be pleased with him) said: Tayammum consists of two strikes: one strike for the face and one strike for the palms up to the elbows. This narration is mawquf (stopping) at Sayyiduna Ibn Umar (may Allah be pleased with him).
Sulayman bin Abi Dawud al-Harrani and Sulayman bin Arqam, who narrated it from the Prophet (peace and blessings be upon him), are both da'if (weak); their narration is not used as evidence.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 997