HERCULES Series 880 lb. Capacity Padded Ergonomic Shell Stack Chair with Metal FrameStudents sit most of the day, provide comfortable seating in your classroom or training room with these popular ergonomic plastic stack chairs. These student stack chairs are favorable in classrooms due to their ergonomic seat shell and lightweight design to move easily around the classroom. The ergonomic comfort formed shell has a waterfall edge to reduce leg pressure and an air vented lower back. Plastic chairs are easy to clean for high traffic