With A. Lange & Söhne Guarantee booklet, Richard Lange model operating instructions, polishing cloth, black presentation box and outer packaging.
The Richard Lange model pays tribute to Richard Lange (1845-1935), eldest son of the company's founder Ferdinand Adolph Lange. Richard is said to have devoted his watchmaking career to scientific research for higher precision in watches. He is accredited with the discovery of a metal alloy for watch springs for which he was granted Patent No. 529945 in 1930.
The present watch model is regarded as the manufacture's first fine observation wristwatch and features a hack feature or stop second option. When the crown is pulled out, the blued steel sweep centre seconds hand and the balance are stopped, thus allowing the watch to be synchronized with a time signal. For further precision measurement the dial is divided into outer 1/6th seconds intervals.