WISE surveyed the entire sky in four broad near-infrared and mid-infrared bandpasses, including W3 = 12μm. Raw W3 imaging contains a wealth of information about the small-angular-scale emission from polycyclic aromatic hydrocarbons in the interstellar medium. However, there are also many contaminants. We have isolated the W3 cirrus by PSF subtracting pointlike sources, correcting bright source artifacts, masking resolved galaxies and moving Solar system objects, and eliminating time-dependent artifacts, among other processing steps. Much of this custom processing was performed at the single-exposure "L1b" level. We stacked our custom-processed L1b exposures on the footprints of 430 12.5°×12.5° "WSSA" tiles to produce a full-sky map. Importantly, this map has been smoothed to 15'' from the native 6'' W3 resolution. The zero-point on scales larger than 2° is derived from Planck 350μm. The WSSA tiles each have several extensions, including bit-masks. Table 2 and Table 3 of the paper provide mask bit and extension descriptions and are reproduced in the README.