Light hangers are used to connect to grow light reflectors to keep the light in exactly the right spot. Use a hanger connection on each side of the reflector to make sure it doesn't rotate around a point. Chain is the cheapest and easiest way to go, just use pliers to open and close the loops. Yoyo hangers are some of the easiest too, simply loosen the butterfly nut to adjust their height. Rope ratchet hangers are used for the heaviest lights and carbon filters.