This classic device is the perfect size to hold a small volume of sample - about 6 ml. The shape and configuration of the shallow, etched groove (1/8" deep and 3/16" thick) help locate specific areas on the chamber. A compact 3-1/2" by 4-1/2" in size, it slips easily under a dissecting microscope. Straight sides mean you don't have to focus up and down. Rounded edges prevent specimens from catching.