The firmness of the pillow will be determined based on the amount of water you fill the pillow with. Like a softer pillow? Use less water. Like a firm pillow? Add more water. We recommend starting with 3 quarts of water. If it feels too hard, remove some water. Not firm enough? Add more water in. We recommend adding or removing the water a little bit at a time to find your comfort level the fastest.
Please note: Maximum capacity of the Water Bag is 5.5 liters.