have a nice Stahlwillie one, very thin walled ( which is why I bought it in the first place )
Being hairy faced ( to hide the spots ) I just walked into the tool shop, bolt in hand and asked for the strongest smallest finest spannars they had in these sizes cuase they had to fit in the tool kit.
That was 1968, they cost more than a weeks wages, but I still have ll of them now so well worth the money in the long run.