The Royal Oak Ultra Thin Tourbillon Openworked was introduced in 2012 as a limited edition of 40 pieces in honor of the 40th anniversary the Royal Oak. It pairs the classic Royal Oak aesthetics with an elaborate hand-wound, open-worked movement with tourbillon escapement. The present 26513BA.OO.1220BA.01 features a yellow gold case and matching bracelet. It was added to the collection in 2016.
