Developed for use in any learning environment, this smooth back stacking chair is maintenance friendly and easy to clean. With the comfort of students in mind, it's unique shape provides lumbar support while offering just the right amount of flexibility. Specifically designed with a smooth back patented flat ribbing support system through the center back of the seat referred to as the “Power Rib”. The “Power Rib” is essential to achieving the ribless design that has the results of durability, comfort and strength. Explorer is a perfect stacker with integrated locking pockets molded into the seat back creating a Channel Lock Stability system. Stack 8 high for convenient storage.