OMGA Copper
Coil in the shape of a ‘foot’ with yellow threads. The ‘OMGA’ copper coil was used from the mid 1960s until the beginning of the 1980s, especially in France. It was available in four sizes, with varying levels of pulverised copper content. This coil could be worn for five years or more, since its copper content did not decrease over time – unlike other types of coil used back then. The body itself was made from flexible plastic, and so it could be inserted easily.
R. Malgouyat: Compt Ren Soc Franc Gyn 1968, 4
G. Espagno et al.: Contracept Fertil Sex 1982 Mar;10(2):151-63