Knowledge is the light in the darkness of ignorance. These flat icons work the same: they highlight your designs in a huge flow of the other ones. Especially, when you can get them for free!
Maths, space, chemistry and physics-related 50 flat icons are carefully arranged in this huge pack. Available in two versions, they're scalable and color-customizable. If you can't do without nerdy odds and ends in your project, then this collection is just what you need for apps, website landing pages, presentations, blogs, infographics and anything your geeky mind can generate!