CLOSE RANGE VISUAL ACUITY CHART, Multi-function visual beacon, multi-angle base, magnetic design REMOVABLE BRACKET SUPPORT, Can be placed horizontally or vertically to provide battery energy INTERCHANGEABLECHARTS FOR MULTIPLEFUNCTIONS, Magnetic cover can be removed and replaced to meet a variety of work needs working distance 25cm super thin frame design brightness:80-320cd/m2 input voltage:110v/220v /60Hz output voltage:DC5V, 1000mA Note: Be sure to remove the battery when the plug is powered. otherwise it cause damage! Please check as much as possible to make sure the item is what you need. Tips:The product may be updated constantly ,Due To Different Batches, The Actual Product May Have Slight Differences Or Color Differences, Which Does Not Affect Use. Colour:White Material:ABS Package Contents: 1 * Near Vision Chart Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.