Zippi Stack Chairs ensure there's always a seat available and add a little zip to every workday. Ideal for providing extra seating in an office, conference room, training room, waiting room or breakroom. Plastic seats and backs are accented with straight-leg, silver powder-coat frames. Backs have perforated slits for ventilation. Four casters allow easy mobility wherever seating is needed. Each seat supports up to 250 lb. Stack up to six high for space-saving storage.