Wow ! That's definitely a beautiful, unique stack! Do they overlap at all?
Not really! The Clash is size 16 and Ecrou is size 17. Clash runs big: Love 16 is a bit too small for me but Clash is comfortable. Initially I had Ecrou in yellow gold size 18 but exchanged it to pink gold 17. I find that they sit comfortably on the wrist together with enough movement for both but without overlapping.