specifications︰ 1.Illumination Source: 3.5V/2.8W halogen bulb;
2.Recharging Unit;
3.Input Voltage: 220V ±10%V;
4.Input Power: 8VA;
5.Diopter Compensation: 0,±1,±2,±3,±4,±5,±6,±8,±10,±12,±16,±20,-25(D);
6.Illumination Form: big spot, small spot, slit, central network, red free;