It's a logo for an LED diode. It is made up of a rectangle with two lines going down vertically to form a base with a half circle on top of the rectangle where the light would be.
This LED Diode icon is a responsive icon. This means that it's optimized for four resolutions, from tiny 16x16 until highly detailed 80x80. The style comes from the latest Microsoft Office
, which makes it perfect for any Windows applications, in particular, those with ribbon toolbar control. Unlike other icon packs that have merely hundreds of icons, this monster icon pack contains 15,900 icons, all in the same style and quality.