From Fallen London Wiki

It's not, it's just that FL images have a normal and a small version and while the game uses the small one for equipment the wiki uses the normal one (looks better). There's normally no big difference, the small is just scaled down, but rarely it can be a tiny cut of a specific part like in this item's case. You can spot the small image (the one you'd see in your inventory) around the middle part of the icon here.