We like these Superworm Bowls because they are functionally perfect in several ways. Since we’re feeding a specific number of superworms per day, we can be certain that with the Superworm Bowl they don’t get lost in the habitat and our dragons can find them readily. The Superworm Bowls are just tall enough so that the superworms don’t get out, but still are a comfortable depth for the dragons to reach in for them easily. The Superworm Bowls are also heavy enough so that the dragons don’t knock them over. These Superworm Bowls are ceramic. We do recommend washing by hand to avoid chipping. The Superworm Bowls measure 3-3/18” in diameter by 1-3/4” in height. Carolina Custom Cages is a division of Carolina Designer Dragons, Inc.