"I heard Abu Safwan say: 'I bought a pair of trousers from the Messenger of Allah before the Hijrah, and he weighed it for me and allowed me."'
Sunan an-Nasa'i Book 44, Hadith 145
← Previous Hadith "Makhrafah Al-Abdi and I brought some cloth from Hajar, and the Messenger of Allah came to us while we were in Mina where there w a man who weighed (goods) in return for payment. He bought some trousers from us, and said to the man who weighed: 'Weigh it, and allow more."'

Sunan an-Nasa'i Book 44, Hadith 144 Next Hadith → "The Messenger of Allah said: "Volume is to be measured according to the system of the people of Al-Madinah, and weight is to be measured according to the system of the peole of Makkah."' (Sahih) This is the wording of Ishaq (one of the narrators).

Sunan an-Nasa'i Book 44, Hadith 146