Nickel Silver 5/16 x 32 Knurled Nut is part of the small detachable brace post assembly

Nickel Silver Nut Stop is part of the small detachable brace post assembly

Nickel Silver Radius 5/16 x 32 Threaded Post is part of the small detachable brace post assembly

This nut is made of nickel silver and has a straight knurl.  the thread is 1/2 x 32 and it is a component of the large detachable brace post assembly   

This post plug is made of brass and fits the large detachable brace post assembly