This is the RM 55 for a buyer who likes a black-strap watch but does not want an uninterrupted dark field around the dial. The white inner bezel gives the openworked layout a visual boundary, so it reads well from normal wrist distance as well as in close photographs. It is a design-led choice, not simply a black-versus-white strap decision.
When comparing options, place the front images side by side before moving to profile shots. Check whether the white ring stays even, whether the dial remains centered within it, and whether the black strap meets the case cleanly. Then use the individual QC set to confirm the exact watch. The RMUL2 manual-winding movement and case material are shown separately in the configuration panel for buyers who want to verify the documented specification.
For a final comparison, check the defining treatment, the case profile and the strap or hardware together in the same QC set. That sequence keeps the buying decision tied to the exact watch pictured and helps separate a genuine configuration difference from a change in lighting or angle. It also gives the buyer a repeatable way to compare sibling pages: use matching views, follow the case perimeter, then inspect the attachment points and visible hardware before deciding.