بسم الله الرحمن الرحيم
والصلوة و سلام على سيد المرسلين و حبيب رب العلمين
Historical Importance of this Durood and the Reason Why it is Recommended by Mashaikh
Once a pious person Hazrat Sheikh Musa Zurair was travelling in a ship when a heavy storm was about to wreck the ship. He was then instructed by the Holy Prophet (in his dream) to read this durood a thousand times. As he finished reading 300 times, the storm subsided and the ship was saved.
It is recommended to recite this salawat 70 times for relief from problems and difficulties.