3M™ Scotchcast™ Soft Cast Tape, Blue, 3 Inch x 12 Foot, 1 Roll 20 30mmHg Knee High Take your measurements 6 inches Color:Yellow Take your measurements 6 inches above mid patella: Extra large is for 23 – 25 1 2 inch circumference LOWER EXTREMITY * Foot Set * Designed to objectively measure volume of the body parts by using the fluid displacement method where the body part is placed in a water filled tank and the resultant overflow is collected and measured * By taking measurements over time edema can be measured and quantified * Includes volumeter overflow cup and graduated cylinder * Cast Tape 3M™ Scotchcast™ Soft Cast 3 Inch X 12 Foot Fiberglass Blue