TinyPNG: Compress PNG & Retain Transparency
Panda just saved you 73% (526kb total)
When you upload a PNG (Portable Network Graphics) file, similar colours in your image are combined. This technique is called “quantisation”. Because the number of colours is reduced, 24-bit PNG files can be converted to much smaller 8-bit indexed colour images. All unnecessary metadata is stripped too. The result: tiny 8-bit PNG files with 100% support for transparency. TinyPNG
/ht @jasonbarone