Sahib al-Marah a very rare Grammar book

This handwritten book explains the Arabic grammar in detail. It is written by Ahmed bin Ali bin Massoud and has the title Sahib al-Marah. It was translated in many languages including Indian. Because it contents was very difficult it was further explained by Al-Badr Al-Aini in 781 HD (1381/84 AD).The book is dated, but the date is not clearly legible. What is known is that Ahmed bin Ali bin Massoud was born in 700 HD (1284 AD) and the explanation is from 781 HD (1381/84 AD). So, it had to be written in that period. The book has clearly been used and suffered some damage over its lifetime. Considering its age, it is in reasonably good condition. The book is 16,5 by 12 cm.