We sell combination wrench sets for the following nuts and bolts:
AF Combination spanner sets
The tools for UNF and UNC are labeled AF. The abbreviation AF means Across Flat (American), this roughly means "measured crosswise" the wrenches fit UNF and UNC threads. If the caliper indicates 9/16 "(14.2mm) when measuring the head, you should use a 9/16" wrench. So the size of the head is decisive.
Whitworth (WW) Combibation spanner sets
Whitworth (WW) open ended spanner: With the English Whitworth bolts and nuts, it is not the head but the diameter of the bolt that is decisive, so measure the diameter of the bolt first, if it is 3/8 "(9.5mm) you must use a wrench that is suitable for 3 / 8 ". The key width of the key is 18.03 mm.