Learners view the special adaptations aquatic vertebrate have for exchanging oxygen and carbon dioxide, Organ systems are graphically illustrated in 3-D; plus two inset diagrams of gas exchange in the gills and complete skeletal system, Includes 24""W x 18""H model activity notebook with glossary key blackline master and color transparency, American Educational Products have a lead ship time of 21 days, SKU: AMED603