That is what I am assuming they appear bulkier than nitrile gloves and much more sturdy than latex. Where does it say they were disposable nitrile gloves? They appeared to be the thicker bulky not disposable ones.
Ask the FBI they said they were different than the searchers which would be latex or nitrile?
The bulky black ones used in agriculture or the butyl rubber ones used for chemicals or handling things in cold storage, and used commonly in cold weather applications when working on equipment which was my first thought and are not disposable.
Seems a clue to me but ok they are on it and don't need us!
I am familiar with gloves in stores I was looking for a link that described the gloves in question.
all imo
edit to add sample non disposable from Walmart [!] but not what I would call commonly used like a latex, imo
Libman Black Industrial Grade Rubber Blended Reusable Gloves - Walmart.com
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