I did not buy this pillow for the cooling feature which is good because it's not cooling. I bought this because I have TMJ/bruxism and, as a side sleeper, a regular pillow was pushing my lower jaw out of alignment and my jaw, head, neck and shoulder muscles hurt in the morning. This pillow works great for that so I'm keeping it. While the dip is only on the face side of the pillow so it's not reversible, the top part of the pillow is for smaller necks and the bottom is for larger necks. Works for my smaller neck.