My apologies if this has been covered in other discussions, but I wanted to share the following and ask a few questions.

I believe this is from the Kitab al-I'tibar (Book of Contemplation) of Usama ibn Munqidh. However, I may be mistaken.

“So we dismounted, and no sooner had [Saladin] set foot on the ground than he said, ‘Where is thy jerkin?’ Upon my order, my attendant produced it. Taking it out from its leather bag, I pulled out my knife and ripped it at the breast and disclosed the side of the two coats of mail. The jerkin enclosed a Frankish coat of mail, extending to the bottom of it, with another coat of mail on top of it reaching as far as the middle. Both were equipped with the proper linings, felt pads, rough silk, and rabbit’s fur.”

The only phrase for which we have the original language is “rough silk”. This is al-lāsīn, which the author takes to be the silk waste produced in the process of spinning the silk threads from the cocoon.

Does anyone know the Arabic for the other things mentioned, especially "jerkin", "felt pads" and so forth?

My second question is how indicative do you think this would be of armour in western Europe, particularly in regard to the textile armours?

I found this, though it discusses horse armour:
https://journals.openedition.org/cy/3293

Tijfaf would apparently be quilted armour.

Term for gambeson would apparently be al-qutun.