Makers and manufacturers sometimes describe constructions in terms of notional “degrees” covered by one of the methods used, such as a welt. When a method is used for less than the total of 360 degrees, that implies that the rest of the upper is attached by some other method.
For example, many traditional English-made bespoke dress shoes can be described as “270-degree handwelted”, meaning constructed by handwelting from the inner heel breast around the toe to the outer heel breast, but with the heel pegged on.
“360 degrees” may be used to clarify that just one method is used. For example, Clarks classic “Desert Boots” might be called “360-degree stitchdown”, since the uppers are turned out and stitched down even around the heels.
There is less agreement on what “180 degrees” refers to. Logically, this might mean running from behind the inside ball around the toe to behind the outside ball, akin to three-quarter welt. But it’s not widely used.
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