Bauerfeind Sports Compression Arm Sleeve - Long. Bauerfeind works with athletes to design the best products for athletes. The Bauerfeind range is made for the competitor who works equally as hard in training as in the game; made for the amateur or professional who wants improved performance.By studyi ng elite athletes; Bauerfeind sports scientists have created innovative protection for muscles and joints. The line of compression technology improves the flow of oxygen to the body for increased circulation; better endurance; less fatigue and quicker recovery time. 3D Airknit technology is light and breathable; and anatomically designed for the perfect fit. The Compressi on Arm Sleeve boosts circulation; providing more oxygen supply to the muscles. The result is increased endurance; less fatigue and quicker recovery. For sizing: 1) with your arm bent; measure the circumference of your arm below the armpit; 2) measure t he circumference at the thickest part of the biceps; 3) measure the circumference at the thickest part of the forearm.Long sleeve fits 17 1/2 -19 3/4 inch.