This Thunderbolt icon is made in Material Design style developed by Google. This style is based on extremely simplified shapes, thin two-pixel lines, and is optimized for 24x24 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 4,400 icons, all in the same style and quality.
The icon is a logo of Thunderbolt. The icon has a bunker like shape, with what appears to be a long horizontal rectangular window in the center. There is also a lighting bolt with an arrow on the bottom of it, located directly on top of the bunker shaped object.