You got me curious, so I managed to find the source text:

1. Ottoman-Balkan Yaya, early 15th century.

Many Ottoman infantrymen were of Christian origin and this seems to have been reflected in their equipment. This man wears an Italian-style reinforced ‘jacket’ over eastern dress. His feathered javelin with its bag of incendiary material was used against siege-engines, ships, wooden defences or simply to terrify the foe.

2. Turkish Sipahi, c.1400.

Feudal cavalry were the backbone of medieval Ottoman armies. This man wears a ‘turban’ helmet and wields the mace favoured by many Muslim warriors. The opening of his highly decorated mail-and-plate armour is protected by an additional chest-covering medallion, and his horse’s lamellar bard has a cloth covering.

3. Ottoman infantry, early 15th century.

This man is clearly one of the Sultan’s élite. He wears full infantry armour of mail-and-splints, probably designed for siege-warfare. Even his engraved iron shield could resist primitive firearms. His sword is slung from his shoulder, a style only used by foot soldiers.

https://www.ospreypublishing.com/uk/osprey-blog/2015/the-armies-of-the-ottoman-empire-an-illustrated-history/