Part Number 302629 Rex 500 What Is The Word BNC Part Number Stand For? And What Type Of The Material That They Used?

What is the word BNC part number stand for? and what type of the material that they used? - part number 302629 rex 500

I make some small changes in light aircraft and found the hall. I know the type of material used and the first time I encountered this example, room number. BNC Luke figures. I used to work with an alloy Alclad 2024 or 7075th The material came from Butler National Constitution (Avcon Industries), U.S.. Then an American friend, help! May God bless the United States