The Lymphatic System chart lays out the structure of the system that helps with the body?s defenses against infection and disease. The chart shows the overall system of drainage in the body, the structure of lymph nodes and lymph vessels, and the formation of lymphocytes. Heavy gauge 3ml lamination with sealed edges and two metal eyelets for hanging makes chart highly durable. Write-on/wipe-off with dry erase marker (not included).