This merchandise contains a Lithium-ion battery. Usually do not mix with sound squander stream. Used batteries ought to be disposed of by a professional recycler or dangerous elements handler per nearby restrictions.K?t Qu? X? S? K?t Qu? X? S? Mi?n Nam K?t Qu? X? S? Mi?n Trung K?t Qu? X? S? Mi?n B?c KQXS Các T?nh KQXS ?i?n Toán X? s? ?i?n toán M