Gynecological Eurogine Novaplus T 380 Ag spiral in Normal size with silver. The silver contained in the core of the wire prevents the copper in the contraceptive wire from breaking when it corrodes in the uterus. Silver is a noble metal and is not corroded by the bodily acids present in the uterine fluids. The fact that the spiral copper remains intact throughout the useful life of the spiral is a significant advantage and enhances the safety of the contraceptive effect.