woody1

A 20mm square section leg will always be structuraly stronger than a 20mm diameter round leg because its strength is enhanced by its 4 corners. However the material thickness also has a part to play and for this reason there are some legs on the market that aren,t thick enough, that is if your screwing a 6 or 8mm thread onto them. Preston and Rive have got their accsessories spot on for this application with the exception of the on box extendable legs where again a scew thread directly onto a soft alloy surface is not a good idea. Length of material will also have a bearing on its structural strength equal to its application