Olympic's stackable electric kilns are designed to come apart so that you can easily move them from one location to another and easily work on one section of the kiln without taking the entire electrical system off the kiln. The 18" series is a good starter kiln for the home artist who plans to be firing multiple items at a time. The 23" series generally works well in the school environment or for the home or studio artist who has outgrown the 18" series. The 28" series serves well as a production kiln for the contemporary studio and production potter. All 28" kilns are built with 3" brick whether they are cone 8 or cone 10 kilns. Multiple depths are available for the 18", 23" and 28" kilns ranging from 18" deep to 31 ½" deep.