4980 and 3980 have the same effect of controlling myopia, but the difference is that the former uses scratch-resistant materials, which theoretically takes longer. Personally recommend 3980, because children's degrees are changing and often need to be changed. Cheaper 1000 is more cost-effective. If children are taught not to take it or wear it, they will not be easily scratched. If they have bad habits, it can be avoided even if it is expensive 1000.