"The Messenger of Allah forbade two kinds of garments and two kinds of transactions. As for the two kinds of transactions, they are Mulamash and Munabadhaha. Munabadha is when a man says, 'I throw this garment, and the transaction becomes binding, and Mulamasah is when a man touches it with his had, without spreading it out and checking it, and once he touches it, the transaction becomes binding."
نَهَى رَسُولُ اللَّهِ ﷺ عَنْ لُبْسَتَيْنِ وَعَنْ بَيْعَتَيْنِ أَمَّا الْبَيْعَتَانِ فَالْمُلاَمَسَةُ وَالْمُنَابَذَةُ وَالْمُنَابَذَةُ أَنْ يَقُولَ إِذَا نَبَذْتُ هَذَا الثَّوْبَ فَقَدْ وَجَبَ يَعْنِي الْبَيْعَ وَالْمُلاَمَسَةُ أَنْ يَمَسَّهُ بِيَدِهِ وَلاَ يَنْشُرَهُ وَلاَ يُقَلِّبَهُ إِذَا مَسَّهُ فَقَدْ وَجَبَ الْبَيْعُ