ETA SA 4750

Caliber 4750 is an electric movement manufactured by ETA SA in Switzerland. Launched in 1960, it operates at 18,000 vph and includes Incabloc shock protection, powered by a WD-4 or WD-5 battery. It was the first Swiss electric watch movement, developed by André Beyner and René Besson using a fixed-coil contact-controlled design with a balance wheel and electromagnetic coil. The movement was used by numerous brands in the 1960s but was discontinued after the Ebauches SA introduced the more reliable Dynotron caliber in 1967.