QuickZip's exclusive ComfortCore hybrid cotton fabric are the most perfect bed sheets ever. Breathable, gentle, and OEKO-TEX certified, they’re safe for sensitive skin. All QuickZip separates are available in ComfortCore material in a variety of stylish colors and patterns including Fitted Zip Sheets, Add-on Zip Sheets, Flat Sheets, Pillowcases, and New-Way Duvet Covers.