Nuts & Bolts.
Size: 5/16" x 26TPI x 19mm(Threaded).
           5/16" x 26TPI x 16.2mm(Threaded)
           5/16" x 26TPI x 13mm(Threaded)
Nuts: 5/16" x 26TPI
Quantity: 3
Note:
These are 'shop soiled' items, the bolt tops are chrome, just require a little polish. Perfectly useable.