Originally launched in 1968, this model is celebrating its 30th anniversary in a limited series of 1,000 pieces. Like the original, it has been overseen by the inventor of the perfectly hermetic Vacuum system, H.U. Klingenberg & Vacuum Chronometer Corp., and has preserved its main features: stainless steel case, automatic movement, special design for the case and hands, and a sapphire crystal. All that distinguishes it from the original model is that the fastening system used for the crystal and the crown are made in 750 (18K) gold.