B7G valve base with P.T.F.E. insulation

Ediswan valve base

circa 1900s

Valve base

Lissen valve base

circa 1920s-1930s

Benjamin valve base

circa 1920s

Valve base

Valve base

Lotus valve base

Telsen valve base

circa 1920s-1930s

Ferranti valve base

circa 1900s