... 4.5Ah Ni-MH rechargeable battery. It has the characteristics of maintenance-free, high-energy, long lifetime, light-weight, no leakage, ... of LED is high efficiency of luminescence, save energy, long lifetime(it can be used for more than 30,000 hours)and ... in circuit of electrical source which has high-sensitivity, it could switch off the electrical source within 15 milliseconds automatically ...