Gunners wore morions to see to the handling of their gun and to protect their heads against enemy slingers and bowmen.

Emperor Montezuma, while in Spanish custody, tried to calm a riotous crowd of Aztecs led by his brother by speaking to them. Although protected by the shields of Cortez’s captains, he was killed by a slinger missile thrown by a warrior in his own army. Apparently he did not rate a Spanish morion helmet.

https://www.thoughtco.com/armor-and-weapons-of-spanish-conquistadors-2136508

In that article, they initially say it was the Morion, which leads to the next question: Who’s right?

Later in the paragraph dealing with helmets and other armor, they refer to the salade and the cabasset. Images for both types come up on Duck Duck Go, showing what they looked like. The salade would be described in English as a “sallet” style of helmet, something that those of us who were fond of reading archaic literature written before the Great Dumbening might have encountered.