Sitka Coyote Core Midweight Zip-T with 7S Logo. The CORE Midweight Zip-T features quick-drying comfort stretch mid-weight fleece and a high-zippered neck to keep your active body temperature regulated as the thermometer rises or plummets. Permanent Polygiene® Odor Control Technology and a low-profile flatlock seam construction make this a versatile next-to-skin layer for a wide range of conditions and activity levels.