1/4" Whitworth (BSW) thread hexagon full nuts pack of 25, steel, bright zinc plated.  Whitworth was the old standard British thread invented in the 19th century, but still used even today on cupboard knobs and handles, beds etc.  These are not tatty old stock ones, but newly manufactured in Britain with a very good bright zinc finish.

The bolt which fits into these will have a thread diameter of 6mm.  Measurement across flats (= spanner size) 7/16" (11.1mm).
Big discounts if you buy more than one pack

Free postage UK:- if you need them quickly we recommend you take either the 1st class post or next working day courier option, as 2nd class post can be a lot slower than they claim. (Courier option is to England/Wales mainland only)