Foot Rest Cushion, Half Cylinder Design, for Home and Office (Large 17.7 " Long by 11.8" Wide by 6" Tall) INTUITIVE DESIGN: Dome Shaped Design Helps Distribute Weight Evenly to Relieve Tension on Your Feet and Legs When Sitting for Long Periods of Time HIGHEST QUALITY: Made from Hypo-allergenic Medical-Grade Foam that Won't Breakdown After Use WILL STAY IN PLACE: Non-Slip Tread on Cover Keeps Your Foot Rest in Place on Hard Surfaces or Carpeting A FUNCTIONAL COVER: The Cover is Easily Removable with Full Zipper and is Machine Washable SIZE CHOICES: Because Some of Us Are Tall and Some of Us Are Small. Dimensions of Large: 17.7" X 11.8" X 5.9" Dimensions of Medium: 17.7" X 7.8" X 5.9"