can you use a duvet without a filler

Fitted sheets have an elastic to wrap around the mattress and prevent it from moving too much while you sleep. While these sheets protect your mattress from body oils, spills, and other things, using a mattress protector underneath your fitted sheet is a good idea for extra protection. Flat sheets lay on top of fitted sheets to protect your duvet or comforter from body oils and tearing. Not everyone uses these, but we recommend doing so. 

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Cotton and cotton blends dominate the market, the most common blend being cotton/polyester. Cotton provides absorbency and a soft hand, while polyester adds durability and wrinkle resistance.[2] Other common fibers used in the manufacturing of bed sheets include linen, silk, Modal and bamboo rayon, lyocell, Microtex or Microfiber, and polypropylene. Polypropylene (olefin) is a hypoallergenic spun-bound material produced at a low cost and typically used in emergency shelters or hospitals as disposable sheeting.

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