Why Blue and Green Color Anodization for ATS pushPIN™ heatsinks? The colors are actually part of the anodization itself. Anodization is about treating the surface of the heatsink to prevent oxidation of the metal while improving radiation heat transfer of the heatsink. For electronics cooling the advantages of ATS pushPIN™ heatsink families surface anodizing is the dielectric isolation of the cooling components from their electronics environment, and the significant increase in their surface emissivity. The increase in surface emissivity of heat exchangers, electronic cabinets and enclosures, and heatsinks is typically on the order of 0.83 to 0.86. When compared to the emissivity of bare aluminum, which is 0.04 to 0.06, one added benefit is the improved radiation heat transfer from the heatsink that results in lower device junction temperature. Of course, the color, whether black, blue, green or else, has no impact on emissivity, it is the anodization, even clear, that enhances the emissivity.