Our 100% Dupioni Mulberry Silk Duvet Insert is filled with top grade dupioni long-strand mulberry silk, and encased in 100% GOTS certified organic cotton. The silk duvet is soft, fluffy, lightweight yet warm. Both fills and shell are OEKO-TEX certified for not containing any harmful chemicals. ☁️ Details ☁️ - Fills: 100% Double Cocoon (also known as Dupioni or 7A) Long Strand Mulberry Silk - the most premium grade of silk. - Shell: GOTS certified organic cotton, 300 thread count, sateen weave with a natural warm white hue and lustrous sheen. - Design: A tack stitch pattern is employed to enhance fill stability while preserving the duvet's smooth and fluffy texture. The long fibers of genuine long-strand silk naturally adhere to the shell, making the use of large-scale stitching patterns,