All Trumark slingshots are powered by surgical tubing. The tubing is attached to the leather pouch with light-weight, hollow, pin connectors * The RR-2 has a considerably heavy pull. The advantage of the heavier pull bands is that it will shoot the larger 3/8" ammo farther than normal-pull bands so there is more impact when the ammo strikes the target * A 0.4% carbon black jacket has been added to the rubber for the ultimate protection against damaging Ulraviolet light rays. The black carbon helps make them the most durable slingshot bands ever * Both left and right bands are cut from one length of tubing so they are "matched" (balanced) for accurate shooting * This item is not for sale in some specific zip codes