Cartoon Icons

Artist: Robsonbillponte
Iconset Homepage: http://robsonbillponte666.deviantart.com/art/Cartoon-Icons-157748615
License: Freeware
Commercial usage: Allowed

Size: 5 MB

Download : Here

Global Warming Icons

 

Artist: Iconshock (Available for custom work)
License: Freeware
Commercial usage: Allowed 

Size: 326.4 KB

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Elements Icons

Artist: Arrioch (Milos Mirkovic) (Available for custom work)
License: CC Attribution-Noncommercial-No Derivate 3.0
Commercial usage: Not allowed
Size: 314.7 KB
Download : Here