Stalwart Illuminated Magnifier Glass with Recharger Features include:Lens material: glassLens size: 4-InchDiopter: 3 Diopter main lens, 8 Diopter bifocal lens 40 Super Bright LEDsInput Voltage: DC 12VPower: 2.5WWorking time: 2 hours Battery: Ni CdLED Life: 20000 hoursLuminance: 550 LuxAdjustable arm Dimensions: 13 x 6.25 x 14.25-InchIncludes retail packaging