Upgraded Formula, Superior Support: Elviros has upgraded its formula to create a slow-rebound cervical pillow with excellent support. The innovative design enables our side sleeping pillows to naturally conform to your spine's curve, offering optimal support for alignment.It may take 2-4 weeks for your neck to adjust to the pillow’s ergonomic curve. Custom Comfort, Dual-Height Support: Designed for back & side sleeping: Designed for back & side sleeping: Elviros adjustable shoulder pillow features a dual-height bed pillow design. The neck support pillow is suitable for different sleeping positions: back, stomach and side sleeping. Finding the right height can help alleviate sleep issues such as headaches, snoring, and neck pain. Dual Certification, Breathable Pillowcase: The Elviros ergonomic pillow core is CertiPUR-US certified, and the removable and machine washable pillowcase (85% Nylon & 15% Spandex) is Oeko-Tex approved for quality and safety, which is upgraded to Gen-2 with more breathable and skin-friendly fabric. And it also helps reduce heat and wicks away moisture. Memory foam pillow naturally has slight odor, which will dissipate after placing the pillow in a well-ventilated area for 3-5 days. Premium Cervical Care System: This sleeping pillow is ideal for both home and travel. It’s not only great for sleeping but also serves as a backrest while reading, for its innovative curve design provides alignment. Neck foam pillow keeps your head in place, reducing discomfort on the cervical spine, enhancing sleep quality, leaving you feeling refreshed and rejuvenated. Intimate Care: Allow the pillow to expand fully within 48-72 hours after unboxing. Please note that the firmness of the orthopedic pillow varies with temperature and humidity—it feels firmer on cold days but softens with use over time.If you have severe neck problems, use with caution.