Exercise and warm-up all with one system! PowerFingers is lightweight and portable. Each set includes 5 rings in a case; and each ring increases in resistance. Resistance is almost unlimited, up to 125 Multiple Power combos. Ideal for Athletes, Students, Teachers, Coaches, Amateurs and Professionals. PowerFingers are latex-free. Lack of latex keeps PowerFingers delicate enough for intricate finger exercises as well as helping to keep latex allergies at bay. Our product is durable enough for constant stretching/exercising.