The strap continues the case tone instead of introducing a new block of color. That lets the bright elements inside the open dial register first when the watch is viewed closely. At a distance, the dark tonneau has a coherent silhouette suited to everyday clothing. Compared with the white-band version, the black RM 55 asks less of the rest of an outfit while the exposed center keeps it far from plain.
The RM 55 blue strap draws attention outward to its blue band. Choose black when the open center should remain the reason to look twice and the strap should blend into the case.
The RMUL2-style manual-winding layout adds a crown-winding routine to this otherwise quiet presentation. It is an appealing pairing for a wearer who values the exposed mechanical look but wants the color story kept simple.
Before dispatch, our QC team reviews open dial centering, dark case perimeter and black strap attachment.