Founded by Robert Pfaff (date not known), manufacturing of watches with Swiss movements. 1945: Henzi joined the company, and movement manufacturing was started. 1953: The first successful Nanga Parbat mission was equipped with Hercules watches. 1961: Henzi continues the company alone. 1972: Out of business.
Remarks HPP used only movements with Swiss lever escapement, before 1945 of Swiss origin, later from own production. Remarkable is that already in the fourties the movements were equipped with an in-house shock device.