NON-SLIP BOTTOM: The extra large waterproof leg cast cover features a non-slip bottom grip design to add extra friction in the shower to avoid slipping. You can shower and bathe at ease. Waterproof Extra Wide Leg Cast Cover for Shower, Extra Large Watertight Foot Protector Cover with Non-Slip Bottom for Plus Size Adults Surgery Casts Boots, Fits Leg Size 10"-29".