I like rubber bands that are just long enough and heavy enough to hold the comb for a day or 2. When I started, I had some real heavy ones. !/2" wide. problems is that the bees have to cut them out of the hive. Takes them a while. They also have to remove them from the hive. Kind of tough with the big ones. Now I use 1/8" thick, 2" diameter bands. They are big enough to fit on my medium and deep frames and the bees can easily handle them.