The anode and cathode were integrated with the contact lens silicone elastomer (Silastic MDX4-4210,Dow Corning) before they elastomer was cured. First, the elastomer base and curing agent were mixed in a10:1w/w ratio and poured over a 17 mm (43/64″) diameter ball(Davies) that had previously been coated with a thin sheet of Parafilm to reduce elastomer adhesion. Parafilm worked better than mold release sprays to prevent elastomer adhesion and subsequent electrode tearing.