Corning Costar CellSTACK Culture Chambers feature USP Class VI polystyrene construction for excellent optical clarity and mechanical strength. Two 26mm diameter filling ports allow direct access to the chamber bottom, providing greater flexibility for sterile filling and emptying by pouring, pipetting, or via tubing in a fully closed system. Self-venting 33mm threaded caps feature 0.2µm pore non-wettable membranes sealed directly to the caps to allow gas exchange while minimizing the risk of contamination. Caps also prevent pressure buildup during transport.