Answer
At the outset, we wish to point out that hair extension is Haraam (strictly prohibited).
Rasulullah (Sallallaahu Alayhi Wasallam) said, ?Allah curses the Waasilah (person who extends hair) and the Mustawsilah (person who seeks to extend hair).? (Bukhari)
and Allah Ta’ala Knows Best
Mufti Ebrahim Desai