Eye Dropper Tool
Located in the Selection tool palette, the Eyedropper tool copies all properties from a selected entity to another entity. These entities could be lines, fonts or dimensions, among others.
For example, for text the properties include font, size and color. For dimensions it includes text location, font, size, style, colors, line weight, layers and arrowhead on/off.
The Option key brings up the Filter dialog box to sift out unwanted properties for advanced settings.