All Jotco Tank Toppers are made of ½ x 1” galvanized welded wire, assembled in the USA with both the safety of your pet and the most value for your dollar in mind. The 20 Gallon Long Tank Topper 30.5” Long is 12” tall and designed for a standard 30” x 13” x 13” tank. It arrives fully assembled with no extra work for you to set up. Simply let the ramp down and place on top of your tank. Due to the design of the topper all of the bedding stays in the tank, not the topper! Our toppers are also made to last as the only plastic on the cage is the liner to the doors. Everything else is made of ½ x 1” wire which has been proven safe for small animals such as gerbils, hamsters, mice, and any other similar pets, which means that you won’t purchase this topper only to have your gerbil or hamster chew through a plastic ramp and leave a portion of the topper inaccessible. This topper also features two spacious corner doors that allow you to reach into any part of the cage that may need or want to. If you have any questions about any of our products then please feel free to contact us and we will do our best to answer any and all questions that you may have. Note: The glass tank and stand are not included.