Silky-Soft & Breathable - Wrapped up in a 1200TC SQ DM long-staple cotton-blend case with a pre-washed and double-brushed finish, our duvet insert california king is incredibly soft, breathable, and moisture-wicking for a refreshing morning,Cloud-Like Fluffy - We've filled this luxury california king duvet insert with high bulkiness ethically sourced white feather & down fibers to make it blissfully soft, lightweight, lofty, and highly insulating,Without Clumping or Cold Spots - Our hotel collection feather down duvet insert features a 3D-Room box construction, ensuring even distribution of fill to warm you from head to toe. 4 corner tabs are easy to attach to your favorite cover. The double-stitched edges add durability for long-lasting use,Ethical Production - Hand-selected, up to 36 washing and sorting processes make our duvet insert highly clean, free of odors and hard quills, and cruelty-free for allergy sufferers. Approved by OEKO-Tex, RDS, SEDEX, etc,Year-Round Comfort - Our all-seasons feather down fibers comforter achieves the perfect balance of comfort, warmth, and fill-weight to ensure a thermoregulatory sleep space that does not overheat or sweat, perfect for most sleepers year-round use --Whether on cool spring and summer evenings or chilly fall and winter nights