1.D: MEDIUM FIRMNESS, ENHANCED SUPPORT: This is the version—after upgrading the firmness, it now features a balanced, medium feel that meets the needs of most users. If you prefer a firmer side sleeping pillow, choose the Memory Foam option. If you favor a softer pillow, opt for the Polyurethane Foam version. The cervical pillow curve design keeps your body in line. 2.SLOW-REBOUND COMFORT WITH CERTIFIED SAFE MEMORY FOAM:This memory foam pillow features slow rebound, ing excellent support 48-72 hours rebound time. The memory foam core is CertiPUR-US certified. As a versatile sleeping and neck pillow, it naturally carries a slight odor that will dissipate within 3-5 days of airing. 3.BREATHABLE AND REMOVABLE PILLOWCASE: The neck pillow is designed with ice-silk fabric, enhancing breathability for a cooler and more refreshing sleep. Oeko-Tex certified for and quality, the pillowcase a skin-friendly, machine washable experience, ensuring comfort throughout the night. 4.DUAL-HEIGHT DESIGN FOR CERVICAL SUPPORT: SIZE 63(11.5/13.5)40.5cm/25 x (4.5/5.3)16inch (LHW): Back sleepers with cervical issues can benefit from using the higher side (5.3 inches) of the orthopedic pillow, designed with dual horns for enhanced head and neck support, ensuring proper alignment with the body. The neck support pillow is suitable for different sleeping positions: back, stomach and side sleeping. 5.NOTE: Please note that this cooling cervical neck pillow is not intended for medical use. If you have serious cervical issues, consult a doctor before use. It may take 1-2 weeks to adjust when using the pillow for the first time, as your cervical spine needs time to adapt to the ergonomic curvature design.