Combo or combination truss head machine screw. A fastener style I despise and won't use. The existence of the slot should never be allowed for any fastener except a few electrical connections and high end gunsmithing.Gotcha. I don’t know what the fastener is called. Has a head similar to a carriage bolt in shape and depth. I’ll add a pic in a minute to this post.
Edit: I guess it’s just a shallow wide head Phillips!
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