Nivarox balance springs that are still in use today. 1997, Zero reset mechanism. In 1997, A. Lange & Söhne introduced an advanced and elaborate self-winding movement: the Sax-0-Mat calibre features an integrated Zero-Reset mechanism that stops the balance when the crown is pulled and instantaneously moves the seconds hand to the zero position, much like in a chronograph. 2005, Disengagement mechanism. With this invention, Lange's split-seconds chronographs – Double Split and Triple Split – can be activated without causing a decline in amplitude. The mechanism prevents friction loss encountered in conventional solutions by separating the interlocking connection between the rattrapante hands and the chronograph hands on the chronograph centre arbor and on the minute counter arbor when the rattrapante button is actuated. 2008, Stop-seconds for tourbillon. A. Lange & Söhne is the only brand to find a way to stop the oscillating balance inside the revolving tourbillon cage to allow precise time setting in watches endowed with this complication. Pulling the crown triggers a complex lever ensemble that pivots a movable V-shaped spring into the balance rim. It instantly stops the balance. When the crown is pushed, the “brake” is released, and the balance instantly begins to oscillate again. 2018, Triple-split chronograph. In January 2018, Lange introduced the triple-split chronograph, an advancement from Lange's double-split chronograph introduced in 2004. The new chronograph can compare the times of two concurrent events, of up to twelve hours' duration and to the accuracy of one-sixth of a second. Being the world's first mechanical split-seconds chronograph that allows multi-hour comparative time measurements, the watch also features Lange's patented isolator mechanism to preserve the amplitude of the balance wheel while the chronograph is running to ensure precision at all times. Notable models Most expensive pieces On November 12, 2007, an 18K-pink-gold A. Lange & Söhne pocket watch (No. 46177) manufactured in 1904 was auctioned by Christie's for around 0.95 million US dollars (1,057,000 CHF). The pocket watch contains complications such as minute repeater, perpetual calendar, split-second chronograph, and so on. On May 12, 2018, a unique A. Lange & Söhne 1815 "Homage to Walter Lange" made in stainless steel was sold for US$852,525 in Phillips' Geneva auction. This is one of the auction records for Lange timepieces. The proceeds went to Children Action, a Swiss children's relief organization. The watch model was introduced in 2018 to pay tribute to the late Walter Lange. It was