The A. Lange & Söhne Tourbograph Perpetual 'Pour le Mérite' 706.025 was introduced at SIHH as the fifth model in the brand's 'Pour le Mérite' series. It pairs the tourbillon with chain & fusee mechanism to a rattrapante chronograph and a perpetual calendar, resulting in the most complex model in the series thus far. The inaugural ref. 706.025 featuers a platinum case and a silver dial. It is limited to 50 pieces.