If you find that your Hypnos Wool Pillow is too soft or too flat, the Extra Filling for Hypnos Wool Pillow lets you customise your pillow. Simply add more fibres until you find your perfect pillow. The more fibres you add, the firmer and deeper the pillow will be. Made with 100% sustainably sourced wool, these fillings are anti-allergenic and naturally temperature-regulating.