Improve your side-sleeping comfort with the Helix Side Sleeper Knee Pillow. Placed between your knees, it promotes optimal spinal alignment by keeping your hips, pelvis, and lower back in a healthier position through the night. The breathable design keeps you comfortable, and the cover is machine washable for easy care. A simple addition that can make a noticeable difference for side sleepers dealing with hip or lower back discomfort. Ships free and is backed by Helix's warranty and returns guarantee.