Effortless Gap-Filling Support: Our bed gap pillow fits gaps of 0-7 inches, effectively filling the space between the headboard and mattress to prevent items and pillows from sliding off. It features 25D high-density foam for comfortable support, maintaining its shape even with repeated use (Note: let it rest for 48 hours after unpacking). The large-capacity storage pocket, secured by buttons, is convenient for storing items like phones and glasses, and this mattress gap filler can be flipped and combined for different needs. The anti-slip bottom fits snugly with the mattress to prevent movement. The durable, air-layer fabric pillowcase with a detachable zipper is easy to clean and can withstand multiple machine washes.