سَرَابِيلُهُم مِّن قَطِرَانٍ

Their garments will be of Qatiran (pitch),

that is used to coat camels.

Qatadah commented that;
Qatiran (tar) is one of the fastest objects to catch fire.

Ibn Abbas used to say that;

the Qatiran, mentioned in the Ayah, is dissolved lead.

It is possible that;

this Ayah reads as:
سَرَابِيلُهُمْ مِنْ
 
قَطِرَانٍ
 referring to heated lead that has reached tremendous heat, according to Mujahid, Ikrimah, Sa'id bin Jubayr Al-Hasan and Qatadah.

Allah said next,
 
وَتَغْشَى وُجُوهَهُمْ النَّارُ
 
 

and fire will cover their faces,

which is similar to His other statement,

تَلْفَحُ وُجُوهَهُمُ النَّارُ وَهُمْ فِيهَا كَـلِحُونَ 

The Fire will burn their faces, and therein they will grin, with displaced lips. (23:104)

Imam Ahmad recorded that Yahya bin Abi Ishaq said that Aban bin Yazid said that Yahya bin Abi Kathir said that Zayd bin Abi Salam said that Abu Malik Al-Ash`ari said that the Messenger of Allah said,

أَرْبَعٌ فِي أُمَّتِي مِنْ أَمْرِ الْجَاهِلِيَّةِ لَا يَتْرُكُونَهُنَّ 

الْفَخْرُ بِالاَْحْسَابِ 

وَالطَّعْنُ فِي الاْاَنْسَابِ 

وَالاْاسْتِسْقَاءُ بِالنُّجُومِ 

وَالنِّيَاحَةُ عَلَى الْمَيِّتِ 

وَالنَّايِحَةُ إِذَا لَمْ تَتُبْ قَبْلَ مَوْتِهَا تُقَامُ يَوْمَ الْقِيَامَةِ وَعَلَيْهَا سِرْبَالٌ مِنْ قَطِرَانٍ وَدِرْعٌ مِنْ جَرَب

Four characteristics from the time of Jahiliyyah will remain in my Ummah, since they will not abandon them:

boasting about their family lineage, 

discrediting family ties, 

seeking rain through the stars, and 

wailing for their dead. 

Verily, if she who wails, dies before she repents from her behavior, she will be resurrected on the Day of Resurrection while wearing a dress of Qatiran and a cloak of mange.

Muslim collected this Hadith.

Allah said next