Each side of this support pillow is shaped more like a V than a U. I like to place the pillow above the knees and this one puts too much pressure on my thighs and is not comfortable. I returned this HoMedics pillow and purchased the Contour brand, which is shaped more like a U.Contour Memory Foam Leg Pillow with Cover, Ecru/CreamThe Contour support pillow is quite comfortable and provides just the right spacing to keep my knees from touching. It straightens my spine even when I curl up like a baby. I can't sleep without it now!!