Muawwizaat are the important surahs related to provide relief from Black Magic.

Some narrations refer to three Quls (Surah Ikhlass, Surah Falaq, Surah An-Naas) 

Whilst others refer to four Quls, with the fourth being Surah Kafirun.

 

Hazrat Aisha (r.a.) related that "Whenever the prophet (s.a.w.) fell ill, he would recite the Muawwizaat and blow on his hand. Then he would pass his hand all over his body. In his death illness, I used to recite the Muawwizaat and blow in his hand. Then I used to pass his hand all over his body. " (Bukhari and Muslim)