Social & Preventive Medicine Demography and family planning 6d9fc696 In Cu 380A, 380 represents A Number of turns of copper wire B Surface area of CuT in sq.mm C Surface area of Cu in sq.mm D Effective life of CuT in quaers High-Yield Explanation The numbers included in the names of the devices refer to the surface area (in sq.mm) of the copper on the device. Metallic copper has a strong anti-feility effect.Park 23e pg: 496