The Ref. 5227G-010’s hinged caseback opens to reveal the elegant caliber 324 SC. Perhaps, most shockingly, this is the first time a Patek Philippe hinged case back does not have any casemaker or gold marks on the inside or the outside of the caseback. The case construction is simple, elegant, and frankly unlike anything Patek Philippe has ever done before. The smoothness and sturdiness of the hinge meshes perfectly with the weight and feel of the caseback. It is simply a masterpiece of modern case production.