Chadar is just a gift as like we present something to someone it is made of cloth a flat cloth piece in radius of 42 meter and weight 20kg approx. People presents these kind of works because they think if we present chadar in Dargah Shafee so at that time and after the Sahib e Mazar will remember us because the gift is touching the Kabr of Sahib e Mazar and it is true that they Oliya Allah are alive.
وَلَا تَقُولُوا لِمَن يُقْتَلُ فِي سَبِيلِ اللَّهِ أَمْوَاتٌ ۚ بَلْ أَحْيَاءٌ وَلَٰكِن لَّا تَشْعُرُونَ - 2:154
Translation: And do not say about those who are killed in the way of Allah, "They are dead." Rather, they are alive, but you perceive [it] not.