Sets of six steering diodes and an ungated Thyristor are simultaneously formed into surge protection circuit modules by mass production techniques. An extended lead frame is provided with three spaced parallel leads for each module. The leads are connected at one end by a bridge. The sets of components are arranged along the lead frame in a fixture. By heating, each lead is soldered between a pair of steering diodes and the steering diodes on each side of the lead frame are soldered to different conductive plates. A thyristor is soldered between the plates. The partially formed modules are removed as a unit from the fixture and may be encased simultaneously. The bridge is removed to separate the modules and the leads trimmed and bent as required.