Lever press. A lever-press box (also known as the Skinner box, operant chamber, or automated problem box) is an environment in which the animal learns to manipulate some device to obtain a reward. The apparatus is fully automated and can accommodate a wide range of experiments. In addition to versatility, an advantage of the apparatus is that it facilitates species comparison because it minimizes species-typical behavior patterns. The latter strength is also a limitation for those interested in species typical behavior. The measure of performance is usually rate of response. Examples are available for bees, cockroaches, crayfish, molluscs, and snails.