The six items are large and small nuts and copper washers for the longitudinal stays. Bottom right is a copper stay used to join the inner and outer firebox plates, thus the two threads. On the left is a patch screw that will be used on the replaced plates on the firebox outer wrapper in lieu of rivets. This is because one end is inaccessible with this kind of repair and so a rivet head can not be formed.
Credit: Dick Bellchambers, 7 September 2005