The lug is the horn that holds the strap or the end link. Its curve decides whether a strap leaves the case cleanly. On a used watch the inner corner of the lug, where a spring bar sits, is the first place a strap stains the metal. Look there for a dark line. A dark line is contact, not a story about origin. If the watch is on a strap, see whether the strap fills the gap between the lugs or leaves daylight on both sides. Daylight means the strap is narrow for the lug width. That is a fit note. It belongs with the diameter and the lug-to-lug length, because those three numbers together describe how the watch meets the arm.

How it differs

A rotating bezel adds height you feel before you see it. Note the height separately from the diameter so the two facts do not get collapsed into one. For the Audemars Piguet Royal Oak 15510 42 Mm, keep the comparison inside this case idea and do not borrow a paragraph from the neighboring model.

Common mods

A previous owner may have polished the tops of the lugs. A flat top where a curve should be is the sentence. Do not invent a reason. On the Audemars Piguet Royal Oak 15510 42 Mm the useful sentence names one changed part.

What to check on a used piece

Compare the left and right end links. Asymmetry there is more useful than a general remark about condition. Apply that list to the Audemars Piguet Royal Oak 15510 42 Mm and stop when the three checks are written.

A library page is written by {Site}. A photo post is one person’s notes. Neither authenticates a watch, offers it for sale, or speaks for the name on the dial. These notes are not authentication and not a shop.